Before it was hijacked by the peddlers of effect-laden blockbusters, science fiction was one of Hollywood's more thoughtful genres. Nowhere else were the big questions of existence tackled with such ingenuity and accessibility. But once George Lucas ventured into a galaxy far, far away, screen sci-fi was overrun with old-fashioned boy's own adventures set in outer space and the focus on spectacular action left little room for intelligent speculation about the nature of life, the universe and everything.

What was so dismaying about this Star Wars effect was that it killed off a reflective brand of science fiction that considered the problems that humanity might face in the near future. Among this last wave was Douglas Trumbull's Silent Running (1972), which was set in the then distant year of 2008 and imagined an environmental catastrophe that had left Earth habitable, but stripped of vegetation. Detractors have pointed out that such a situation would deprive the surviving populace of necessary oxygen and screenwriters Deric Washburn, Michael Cimino and Stephen Bocho are also guilty of making little attempt to produce a backstory that would plausibly justify the command orders that would turn a mild-mannered botanist into a killer.

In order to preserve the planet's last remaining flora and fauna, the authorities dispatched a fleet of space freighters into orbit near Saturn carrying their precious payloads in geodesic domes that acted like giant greenhouses. However, the powers that be decide to abort the mission and return the craft to commercial operation. Botanist Bruce Dern deplores the directive, however, and not only refuses to destroy the cargo aboard the Valley Forge, but also kills astronauts Cliff Potts, Ron Rifkin and Jesse Vint and stages a fake explosion to convince his superiors that their orders have been faithfully executed.

Dern plots a new course and enlists service robots Huey, Dewey, and Louie as his gardening assistants. He even rewires them to perform surgery on a leg injured in his battle with his crewmates and consoles the other two when Louie is lost during a bout of turbulence while attempting to navigate through Saturn's rings. Undeterred and dressed like a latterday St Francis of Assisi, Dern tends to his trees, plants and animals with a devotion that the remaining drones come to share. He is less successful in teaching them to play poker, but is moved by Dewey's concern for his friend when he undergoes repair after Dern crashes into him in his buggy.

Yet, despite his unceasing efforts, Dern cannot prevent the forest from deteriorating and it takes him a while to realise that he needs to increase the vital light supply. However, his discovery coincides with the search vessel Berkshire making contact with him and he opts to take drastic action in a desperate bid to save the dome and its irreplaceable contents.

There's no escaping the fact this is a hugely sentimental story, with the anthropomorphisation of the drones increasing the kitsch quotient. The script is also stuffed with bad science and liberal kitsch that is exacerbated by Joan Baez's cornball lyrics on the soundtrack. But Dern's interaction with Huey, Dewey and Louie (who were controlled by bilateral amputees Mark Persons, Cheryl Sparks and Steven Brown) is charming and makes for compelling contrast with Keir Dullea's interaction with HAL in Stanley Kubrick's 2001: A Space Odyssey (1968).

Trumbull had created the special effects for the latter and he works minor miracles on a much smaller budget to capture the foliage against the interstellar vistas and display the meticulous authenticity and orbiting elegance of the Valley Forge models. Moreover, he also anticipated many green concerns in stressing Dern's preference for fresh produce over flavourless processed sustenance. But the message is never hammered home and, while the science and the scenario may be flawed, the poignant sight of Dewey floating alone in space may well provoke more discussion about our stewardship of our fragile home than any number of earnest eco-documentaries hectoring viewers about their culpability for global warming.

Released two years later, Francis Ford Coppola's The Conversation (1974) also has an eerily contemporary ring to it, thanks to the ongoing phone hacking scandal. In some ways, the concept of privacy seems oddly anachronistic in an age when so many people broadcast their every waking thought and movement via mobile phones and social network sites. But the fear of being eavesdropped upon remains potent and Coppola (who wrote his screenplay in the late 1960s) brilliantly anticipated the mood of paranoia that would engulf the United States following the revelation of the Watergate break-in and President Richard Nixon's involvement in an attempt to bug Democratic Party headquarters. However, this is much more than a zeitgeist piece, as Coppola and Gene Hackman also created one of the most memorable characters of the entire New Hollywood era in surveillance expert Harry Caul.

Personifying the nondescript in his spectacles and plastic raincoat, Caul is so fiercely protective of his privacy that his San Francisco apartment is triple locked and contains only a saxophone and a statue of the Virgin Mary. His business premises are equally impregnable, with his office being enclosed within a wire mesh inside a cavernous warehouse. All his calls are made from pay phones and even his trysts with mistress Amy (Teri Garr) take place in her secluded basement. Yet, despite constantly reminding sidekick Stan (John Cazale) to avoid becoming personally involved in cases, Caul is haunted by the fact that an exchange he recorded resulted in the deaths of three people and this terror of causing another fatality prompts him to become obsessed with a conversation in Union Square between Ann (Cindy Williams) and Mark (Frederic Forrest) that includes the chilling line: `He'd kill us if he got the chance.'

Desperate to verify what he heard and ascertain its precise meaning, Caul spends hours modulating the different recordings captured by his operatives and soon comes to realise that such is the nuance of the delivery and the intensity of its sonic context that the sentence takes on new meaning with each hearing. Time away at a bugging convention does little to raise Caul's spirits, especially when he is humiliated by New York rival Bernie Moran (Allen Garfield), who hides a microphone on his person and plays back Caul's feeble attempts to pick up a woman. However, his crisis intensifies when he returns, as his client (Robert Duvall) sends assistant Martin Stett (Harrison Ford) to bring back the tape that Caul is intent on withholding.

Something has to give and Caul can only listen in horror, as the consequence of the conversation plays out in a downtown hotel room. But the final blow to his tottering edifice of self-preservation comes from an entirely unexpected source and, in one of the most iconic closing shots of the entire decade, he is left sitting in his ransacked apartment playing his saxophone in inglorious isolation.

So many aspects of this film are impeccable. Bill Butler and Haskell Wexler's cameras suggest something is lurking behind every corner and in every shadow of Dean Tavoularis's production design, while David Shire's music echoes Caul's growing psychological strain. But it's Walter Murch's masterly sound design that makes this so oppressive and sinister, as it gives the audience an intimate insight into Caul's sensory torment in much the same way that Michelangelo Antonioni's use of space and angle allowed the viewer to share London photographer David Hemmings's bafflement as he searched for murder clues in Blow-Up (1966).

Coppola utilises his San Franciscan locations with equal efficacy to make what had been the city of peace and love just seven years earlier seem like a hot bed of corporate malevolence and soul-destroying alienation. But, despite his teasing manipulation of deceit, delusion and ambiguity, it's the way in which Coppola induces pity for an entirely unsympathetic character that most impresses. Mistrusting everyone and everything, Caul has even abandoned his Catholic faith in his pathological determination to eliminate potential weakness. Yet, ultimately, he proves vulnerable to be a damsel in distress and his failure to be her silent knight provokes his inevitable breakdown and not even the sound of his saxophone can drown out the unrelenting admonition of his conscience.

Coming between the first two parts of the Godfather trilogy, The Conversation won the Palme d'or at Cannes, even though it proved something of a commercial misfire. By the time, Coppola made One From the Heart (1982), however, he was still recovering from the trauma that was Apocalypse Now (1979). Unfortunately, fashioning a quaint romance set on the Fourth of July turned out to be every bit as fraught as countless months spent in the jungles of the Philippines attempting to recreate the madness of the Vietnam War.

The story couldn't be more simple. Scrapyard worker Frederic Forrest and travel agent Teri Garr have gone to Las Vegas to celebrate their fifth anniversary. However, Forrest teases Garr about her longing for some once-in-a-lifetime excitement and she abandons him to go in search of her dream lover. She finds him in Latino waiter Raúl Julia, while Forrest finds consolation in circus tightrope walker Nastassja Kinski, who loves the illuminated wonderland he has created in his garage from parts salvaged from the yard. But, while Garr makes plans to go to Bora Bora with Julia (who has grand ambitions to become a musician), Forrest comes to his senses and realises how much he loves her.

He tracks her down to Julia's apartment and insists she comes home. However, Garr is adamant that the relationship is over and heads for the airport to embark on her cherished romantic odyssey. In desperation, Forrest follows her to the terminal and begins singing to Garr in the hope of proving that he is still her soulmate and is capable of touching her heart. But she boards the plane. The distraught Forrest returns to the empty over her abandoned clothes with the intention of torching them when Garr prefigures by almost two decades Jennifer Aniston's dramatic entrance in the final episode of Friends.

Only Coppola will know how a small movie budgeted at $2 million ended up costing over $25 million. In deciding to construct stylised sets in his Zoetrope Studios instead of shooting on location, Coppola clearly hoped to recreate the magic of the old MGM musical. But, wonderful though Dean Tavoularis's set were - especially when they were so enchantingly lit in atmospheric neon by Ronald Víctor García and Vittorio Storaro - they couldn't turn a mediocre melodrama into a masterpiece. They could, however, tip Coppola into bankruptcy and he not only lost his studio, but also spent much of the next 15 years as a director for hire to pay off his debts.

The film has a diffuse charm, with the soundtrack by Crystal Gayle and Tom Waits being particularly engaging. But the imagery overwhelm the story - as New York Times critic Janet Maslin put it, `it's as if Rembrandt were painting Easter eggs' - and it's difficult to care what happens to any of the central quartet, let alone peripheral best friends played by Lainie Kazan and Harry Dean Stanton. The screenplay is largely devoid of the screwball wit it so calculating strives to emulate, while the performances are so achingly sincere they often become excruciating. Yet this can still surprise with its beauty and vainglorious audacity, even though there is something desperately sad about seeing a visionary fall so far short of what he had envisaged and pay such a colossal price for his folly.

It was evidently a chastened Coppola who embarked upon the 1983 adaptation of the cult rite-of-passage novel, The Outsiders, which SE Hinton had written 17 years earlier when she was still a teenager herself. Indeed, he was persuaded to make the film by a class of Californian schoolkids and considerably reworked Kathleen Knutsen Rowell's screenplay to suggest that the adolescent American males currently lapping up every action romp concocted by contemporaries Steven Spielberg and George Lucas were also capable of a little bit of poetry and sincere emotion. The result was decidedly mixed and the target audience was largely put off by the touchy-feeliness of what was essentially a bromance. But Coppola succeeds in paying handsome homage to the teenpix of his own youth, most notably Nicholas Ray's Rebel Without a Cause (1955).

In Tulsa, Oklahoma in the 1960s, two gangs from different sides of the tracks are vying for supremacy. The Greasers are from the tougher, working-class neighbourhood. They are led by the Curtis brothers - Sodapop (Rob Lowe), Darry (Patrick Swayze) and Ponyboy (C. Thomas Howell) - and include Johnny Cade (Ralph Macchio), Dally Winston (Matt Dillon), Two-Bit Matthews (Emilio Estevez), and Steve Randle (Tom Cruise) among their number. The Socials are fronted by Bob Sheldon (Leif Garrett) and Randy Adderson (Darren Dalton) and they pick a fight with Johnny, Ponyboy, and Two-Bit after they catch them flirting with their girlfriends, Cherry (Diane Lane) and Marcia (Michelle Meyrink), at a drive-in movie.

The `Soches' don't forgive the intrusion, however, and Bob and Randy attack Johnny and Ponyboy in the park. But Bob is killed when Johnny pulls a switchblade and the pair are forced to hide out in an abandoned church. Johnny reads Gone With the Wind and some poems by Robert Frost to pass the time before Darry arrives with the good news that Cherry will testify on their behalf if they are charged with Bob's death. However, on returning to the church, they find it is on fire and Johnny is badly injured in rescuing some children trapped inside.

The authorities bring a charge of manslaughter against Johnny, while Ponyboy is threatened with being taken into care. But the Socials want revenge for Bob's demise and call for a rumble, which they promptly lose. Johnny is unimpressed by the victory, as he lies dying in hospital and Dally is so distressed by his death that he gets himself killed trying to rob a grocery store. Ponyboy has learned his lesson, however, and devotes himself to his studies after finding a note inside Johnny's copy of Margaret Mitchell's novel in which he says that he is glad he perished finally doing something worthwhile.

Some three decades after it was released, it is almost impossible to be moved by this melodramatic and relentlessly sentimental picture. The performances are laudably earnest (although it's often distractingly hilarious noticing the tics and traits that the young actors would retain into adult stardom) and Stephen H. Burum's widescreen photography brings a certain grandeur to proceedings. But Coppola's storytelling is as clumsy as father Carmine Coppola's grandiloquent score and Marjorie Bowers's clichéd costumes, with events tumbling in on one another with a scurrilous disregard for pacing or characterisation. Consequently, any semblance of real life is suffocated by a stylistic excess that smacks much more of 50s Tinseltown than 60s authenticity.

Coppola undertook producing duties on the week's other two titles, Caleb Deschanel's The Escape Artist and Wim Wenders's Hammett (both 1982).

The first marked the directorial debut of an acclaimed cinematographer who was Oscar-nominated for his work on The Right Stuff (1983), The Natural (1984), Fly Away Home (1996), The Patriot (2000) and The Passion of the Christ (2004), but curiously not for his finest achievement, The Black Stallion (1979). However, Deschanel would only emerge from behind the camera to occupy the director's chair one more time on Crusoe (1989) and it has to be said that he is much better at framing the shots than calling them.

Adapted from a novel by David Waggoner, the story centres on teenager Griffin O'Neal, whose late father was billed as the second greatest escapologist after Harry Houdini, and opens with him issuing a challenge to the local cops that he could break out of their most secure cell. An extended flashback fills in the background by showing how O'Neal ran away from his grandmother's house to perfect his magic tricks on the road with vaudevillian aunt and uncle Joan Hackett and Gabriel Dell, who have a mind-reading act.

However, while he is a gifted performer, O'Neal also has a talent for trouble and he soon makes an enemy of small-town mayor Desi Anaz and his loose cannon son, Raúl Julia, who divides his time between dating Teri Garr and poking his nose into other people's business. O'Neal takes such a dislike to him that he picks his pocket and the stolen wallet becomes key to exposing the corrupt nature of Arnaz's regime and promoting O'Neal's fledgling career.

Co-scripted by Melissa Matheson, who had just completed ET The Extra Terrestrial, this is a muddle from start to finish. O'Neal's voice-over is used to ease the narrative through its less convincing moments, while the structuring of the action around a flashback that accounts for much of the running time ensures that the denouement seems resoundingly anti-climactic. Even Dean Tavoularis's production design feels haphazard with various period styles clattering into each other in a bid to evoke an Anytime America.

Nevertheless, Deschanel and cinematographer Stephen H. Burum achieve some lustrous images and Georges Delerue's score is a jaunty delight. It's also nice to see such Hollywood veterans as Jackie Coogan and Huntz Hall in supporting roles, along with dependables like M. Emmet Walsh and a young Elizabeth Daily, who steals scenes as O'Neal's waitress girlfriend. O'Neal holds his own, but he simply doesn't have the charisma of his father Ryan or the presence of his sister Tatum. Consequently, Arnaz and Julia run rings around him and this further upsets the balance of an already precarious picture.

Perhaps the most controversial picture produced at Zoetrope in this period was Hammett. Based on a novel by Joe Gores, it was designed to explore the links between life and art by showing how ex-Pinkerton agent Dashiell Hammett was inspired to write the classic Sam Spade thriller, The Maltese Falcon. Having already demonstrated his fascination with Golden Age hard-boiled Hollywood cinema in features like The American Friend (1977), German director Wim Wenders seemed the perfect choice to realise the project. But, in his role as executive producer, Francis Ford Coppola became so concerned by the direction the shoot was taking that he ordered numerous retakes and further upset Wenders by imposing his own vision on the final cut. What emerged, therefore, was less a majestic tribute to pulp fiction and old-time movie-making than a technically accomplished and dramatically bankrupt misfire, in which neither Wenders nor Coppola has could take much pride.

Samuel Dashiell Hammett (Frederic Forrest) is a struggling writer pounding out detective stories on his battered Underwood typewriter in a seedy San Francisco apartment. He drinks and smokes far too much for a man battling tuberculosis, but he has turned the head of red-headed librarian Kit Conger (Marilu Henner), who lives in the same Chinatown building. However, any thoughts of romance are shelved by the arrival of Hammett's former Pinkerton boss Jimmy Ryan (Peter Boyle), who wants him to help search for Crystal Ling (Lydia Lei), a Chinese hooker who has disappeared after blackmailing some of the most powerful men in the city.

As he starts his investigation, Hammett learns that Crystal was sold into white slavery by her parents when she was just nine years old and had run away to a dockside mission house to seek sanctuary from her gangster pimps. However, the focus soon shifts away from the missing prostitute and onto the lawmen and lowlifes who seem to be taking an unnatural interest in a case involving a comparative nobody.

Featuring in this gallery of rogues and grotesques are sneeringly corrupt cops mobster Fong Wei Tau (Michael Chow), Lieutenant O'Mara (RG Armstrong) and Detective Bradford (Richard Bradford), shifty pornographer Gary Salt (Jack Nance), and crooked lawyer Eddie Hagedorn (Roy Kinnear) and his shrill gunsel lover, The Punk (David Patrick Kelly). In a nice touch, Wenders also cast Elisha Cook (who had played the latter role in John Huston's seminal 1941 version of The Maltese Falcon) as a subversive cabby, who turns out to be the only person Hammett can trust besides Kit. He also found roles for such studio stalwarts as Sylvia Sidney, Royal Dano, Hank Worden and maverick director Samuel Fuller. But no one really has enough to do, as Forrest makes his rounds of cheap dives and seedy alleyways and discovers that several civic dignitaries are embroiled in the illegal trading of stag movies and underage girls and that he has been set up to be the fall guy.

If anything, the plot owes more to Robert Towne's scenario for Roman Polanski's Chinatown (1975) than anything Hammett might have concocted and the coarse language would certainly never have been tolerated on either page or screen at the time. But while the action never really catches fire, it always looks superb - thanks to production designers Dean Tavoularis and Eugene Lee and cinematographers Philip Lathrop and Joseph F. Biroc - and is jazzily scored by the peerless John Barry. The performances are also admirable, with Forrest suggesting some of the gutsy charm that Jason Robards had displayed as Hammett in Fred Zinnemann's Julia (1977) and Boyle and Kinnear making the most of what are essentially amusing caricatures. But, as it's difficult to distinguish between the scenes directed by Wenders and those remoulded by Coppola, the film's ultimate failure has to be put down to a clash of egos and the speciousness of the original conceit.