The cash cows that Hollywood keeps on milking

Last summer, movie audiences finally saw how Hugh Jackman got his adamantium claws in X-Men Origins: Wolverine, showcasing the most popular character from Marvel's mutant superhero crew. Right now, in Get Him to the Greek, Russell Brand is reprising his louche British rocker Aldous Snow, hitherto a support act in Forgetting Sarah Marshall and now the headliner. The Shrek series has run its course but Antonio Banderas remains adamant that a solo outing for Puss in Boots is still striding forth.

Meanwhile, anyone who witnessed the recent MTV Awards saw Tom Cruise shaking his sizeable booty in the guise of his bilious, bullet-headed, hip-hopping studio exec Les Grossman, his character in Tropic Thunder: a cleverly calculated test-run for MTV / Paramount's recently announced Untitled Les Grossman Project.

Yes, Wolverine is effectively a prequel and Get Him to the Greek is a sequel of sorts. Cruise's Grossman film could go either way. But they're all examples of the spin-off, Hollywood's latest bid to work every possible angle from potential franchises.

Spin-offs are not new. What is Mark Twain's 1884 masterpiece The Adventures of Huckleberry Finn, if not a tributary using a character from The Adventures of Tom Sawyer? Orson Welles's villainous Harry Lime, shot dead at the end of 1949's The Third Man, proved so popular that he was resurrected in an early Fifties radio show, The Lives of Harry Lime, based on Lime's earlier escapades and voiced by Welles.

TV shows have played the same game, with varying success rates. For every Frasier, the award-laden Cheers spin-off, there's a Joey, the hapless Friends extension. Yet a hit can yield multiple returns, as evidenced by Happy Days ( Laverne and Shirley, Mork and Mindy) and Doctor Who ( Torchwood, The Sarah Jane Adventures).

Traditionally, movies are different beasts. While sequels and prequels, or "reboots" ( Batman Begins, Star Trek), have been the continuation method of choice, recently the spin-off appears to have woven a cunning web of new strands. Marvel Studios will link its superhero titles – Iron Man, The Incredible Hulk, the upcoming Thor and Captain America – in a forthcoming team effort, The Avengers. The studio's X-Men franchise, despite the dire Wolverine, is attempting something similar, while George Lucas's Star Wars empire has more offshoots than you can shake a lightsaber at.

Given the built-in back-stories and fanbases of superhero and sci-fi franchises, such overlaps and sidebars are understandable. Projects such as Get Him to the Greek seem less certain bets, though creative tweaks cast Brand's Snow as a more tragically aware figure than he was in Sarah Marshall.

Yet regardless of nips and tucks, spin-offs often seem stitched together from spare parts, like Frankenstein's monster. Tommy Lee Jones won an Oscar for his performance as Lt Gerard in The Fugitive, doggedly pursuing Harrison Ford. But when he revisited the character in US Marshals, it was audiences who scarpered, not Ford. The gritty sci-fi Pitch Black kept Vin Diesel's intriguing anti-hero Riddick cloaked in the shadows but the garish The Chronicles of Riddick laid him bare, looking silly.

"I think [spin-offs] can work but there's a fine balance," says the British director Tom Harper, who is currently working on This Is England '86, a four-part TV spin-off from Shane Meadows' acclaimed, largely autobiographical 2006 film. "All too often it happens because producers want to cash in on the success of the initial premise and it's not possible to do any more because actors have gone off or it can't continue in its current form."

The evidence is damning. Did studios seriously feel that audiences craved a continuation to the Jim Carrey vehicle Bruce Almighty, promoting Steve Carell from a small role as a hapless weatherman to Job-like lead in Evan Almighty? Or was Carell, then an emerging star, simply a cheaper replacement for the $25m Carrey? Likewise, recent horror "mash-ups" such as Alien vs Predator had no chance of recruiting stars such as Arnold Schwarzenegger or Sigourney Weaver, nor directors such as Ridley Scott or James Cameron, thereby diluting any potency the originals once boasted.

Harper is adamant that This Is England '86 has sturdier motivations, citing Meadows's commitment (he and Harper direct two episodes each) and a returning cast, including Thomas Turgoose and Stephen Graham,as proof. "It's just Shane going, 'This is unfinished business and there are still some other stories that I'm desperate to tell. So rather than go away and do my next feature, I can't get my head out of this world and this is the story I want to tell,'" Harper recounts. "This cast and this family he's built around him are important and it shows. So hopefully that will make it stand out."

This distinguishing factor is the creation of a world that both creator and audiences can invest in, where characters can co-exist and there's a greater validation for returning to their stories. Kevin Smith's output is hit-and-miss but his "View Askewniverse", explored in Clerks and its spin-off Jay and Silent Bob Strike Back alike, feels more integral and honest. Likewise, the cross-referencing of characters in Reservoir Dogs, True Romance and Pulp Fiction would justify Quentin Tarantino revisiting his creations.

George Lucas or Marvel could use the same arguments for their continued explorations or exploitations of their fictional worlds, of course: it's up to us to decide if they are resorting to thrifty recycling in times of economic austerity, or merely milking the cash cow dry. But when Harper talks of Meadows's "unfinished business", it's clear he means "emotionally". In too many spin-offs and sequels, it's business in the financial sense that keeps the projects turning over and over.

Click here or on the image to launch: Role Revivals: 10 Characters we'd like to see spun off