Modern Hollywood has had a thing for spandex tights and alter egos ever since Christopher Reeve launched into the Manhattan skyline in Warner Bros' 1978 hit Superman.

While subsequent superhero adventures have met with varying degrees of success, there is a level of accomplishment and ambition in recent years that suggests the beginning of a new golden age.

Spider-Man's thunderous $114.8m three-day debut in 2002 for Sony proved a superhero picture can be a thing of beauty. Lately more and more comic-book and graphic-novel adaptations, including this summer's Iron Man from Marvel Studios and Paramount Pictures and Wanted from Universal, have hit the mark.

The trend looks set to continue. Warner Bros' The Dark Knight (released in the US on July 18) tore up the record books with a record $155.3m North American three-day opening weekend. Similarly Universal's upcoming release of Hellboy II: The Golden Army, Lionsgate/Marvel's Punisher: War Zone and Lionsgate/Odd Lot Entertainment's The Spirit have kept devotees buzzing.

The detail and scope of adaptations has broadened in recent years as fanboy directors Guillermo del Toro, Christopher Nolan, Kevin Smith, Zack Snyder and David Goyer, as well as pop-culture fixtures Sam Raimi and David Cronenberg and their counterparts in the agencies and executive ranks, have stormed Hollywood's barricades.

'Anything that's coming from some sort of source material is seemingly what is in vogue,' says Adam Levine, an agent in the literary department at talent agency Endeavor.

Hollywood, always on the lookout for material, is hooked, but it needs to tread carefully. Not every adaptation captures the imagination as Hulk, From Hell and Elektra, to name but a few, have shown.

So how does Hollywood harness the potential of this colourful universe of characters while satisfying the fans, whose opinionated online presence can create a kind of tyrannical hive mind'

'You always have to keep a kernel of truth about the character and story that resonates with the audience while you update the story,' says Stephen Broussard, vice-president of production and development at the now autonomous Marvel Studios.

Scott Agostini of the William Morris Agency agrees. 'If you don't handle certain characters or elements in the right way, fans revolt. You have to get Iron Man right; you have to get the Hulk right. People know Spider-Man, but you'd better have Aunt May and J Jonah Jameson in the story.'

Creative licence

Small changes, it seems, are tolerated. Broussard - whose company's Iron Man kicked off the summer season and has crossed $500m worldwide - recalls when Sam Raimi and former Marvel Studios chief Avi Arad, now an independent producer, sat down to discuss Spider-Man.

They felt it would take too long to explain how Peter Parker engineered his web shooters and decided to make the netting spurt from his wrists organically. Despite initial grumblings from some bloggers, the gamble paid off.

'If you get it right, then little imperfections fall by the wayside,' says Gregory Noveck, senior vice-president of creative affairs at DC Comics, now wholly owned by Warner Bros. 'You can't dupe ardent fans. Even if the actors and director are ready to go, you cannot do it unless you have the right story.'

Noveck is a keeper of the faith of sorts, a conduit between the comic books and his colleagues at the studio. He works closely with Warner Bros Pictures Group president Jeff Robinov, but says his level of involvement depends on the project.

'I'm in touch with all our film-makers,' he explains. 'However on something like The Dark Knight, (director) Chris Nolan is so knowledgeable they don't need me as much. It wasn't hard for things to fall into place on that one and we were fine with Nolan making changes because we knew he was steeped in Batman lore.'

Nolan's co-screenwriter and brother Jonathan Nolan and story writer David Goyer, whose extensive credits include Batman Begins, the Blade series and an as-yet-unfilmed screenplay for The Flash, are also die-hard genre fans.

For the producers on these adaptations, the role is different. 'I felt it was my job to act as the audience and ask questions until we'd worked it all out,' says Odd Lot Entertainment's Deborah Del Prete of her time with director Frank Miller on The Spirit, an adaptation of the classic Will Eisner comic strip. Odd Lot is co-producing with Lionsgate.

The partners screened the trailer and several scenes at Comic-Con in San Diego ahead of the scheduled December 25 US release.

The annual pop-culture jamboree has evolved into a key networking and promotional platform for Hollywood and represents an opportunity to showcase this latest work from Miller, a veteran comic-book writer and artist who co-directed Sin City.

Del Prete had for years wanted to adapt the story of a rookie cop who returns from the dead to fight crime. Her chance came when Michael Uslan, another producer on the film, persuaded the notoriously protective Eisner to allow Odd Lot to option the rights. Miller, an Eisner protege from previous years, came aboard after he and Del Prete struck up a rapport at the Sin City premiere.

They collaborated throughout the development process and the four-month shoot on green screens and black screens at the brand new Albuquerque Studios in New Mexico.

The story stars relative unknown Gabriel Macht as the eponymous hero, as well as Samuel L Jackson as villain The Octopus and an ensemble headed by Eva Mendes, Scarlett Johansson and Paz Vega.

'It has a '40s and '50s look and yet the characters use mobile phones,' says Del Prete of the film's contemporary feel. 'And The Spirit doesn't carry a gun.

Other characters do, but Will (Eisner) always said the city was The Spirit's weapon. You have to stay true to the key elements and not a day went by when we didn't ask ourselves what Will (who died in 2005) would think.'

The big pitch

It helped that Miller personally storyboarded the entire film. The visual nature of comic books and graphic novels gives adaptation pitches a leg-up when it comes to meeting studio executives. 'Any leverage you can get helps,' Endeavor's Levin says, noting this is especially true with an untested property.

'You're always going to have that linear pitch that hits you between the eyes,' says William Morris' Agostini. 'But for stuff that's non-linear, where you're trying to describe a huge universe, a comic book can do the job. There's a kind of reverse engineering at play.'

A film pitch can sell before the comic book has even been written. The comic is then developed to give the film-makers and studio executives a deeper visual understanding of the world.

Scott Mitchell Rosenberg's Platinum Studios, a publicly owned company that controls a library of more than 5,600 largely untapped characters, recently announced it was partnering with Gale Anne Hurd's Valhalla Motion Pictures on the sci-fi thriller Final Orbit, months before Platinum is due to issue the comic book. This is not uncommon. After all, DreamWorks snapped up rights to Shrek based on a slim comic book with few words.

'You want to get your projects set up at studios but it's important to us to be able to package it and find the right home for material,' says Eric Gitter of Oni Press' production arm Closed On Mondays, the company behind titles such as Scott Pilgrim Vs The World and Resurrection.

'The studio takes the underlying rights but you're always a participant.'

Agostini adds: 'The deals can get complicated. In most cases I will have a comic come in and I will go out and find a group of producers. If I can get a high-level producer like Michael Bay, Bryan Singer or Lorenzo Di Bonaventura, I will attach them.'

Agostini has brokered many deals in this space and set up Alexis Nolent's French titles The Killer with Plan B at Paramount for David Fincher to direct, and Cyclops at Warner Bros for James Mangold. Alexandra Milchan is producing both.

'Once the producer is on board we get a writer in and pitch to the studio, which will try to obtain a licence for underlying rights to the property,' Agostini explains.

This grants sequel rights, which generally need to be exercised within a certain timeframe before reverting to the rights holder. A sequel gives a film-maker a second bite at the cherry. Lionsgate optioned the rights to Marvel's The Punisher series, a dark revenge episodic that was most recently adapted into the 2004 release of the same name starring Thomas Jane, and returns this year with Punisher: War Zone.

Producer Hurd, whose credits include this summer's The Incredible Hulk as well as The Terminator, Armageddon, Aeon Flux and Hulk, produced both The Punisher and Punisher: War Zone. 'There's a desire to continue to bring the Punisher to the screen and respond to the fans' requests that the film be even more graphic and true to the comic-book series,' she says, adding that director Lexi Alexander (Green Street) was 'on the same page' about taking the story in a darker, more intense direction.

Jane was unavailable to reprise the role so the film-makers brought in UK actor Ray Stevenson, whose credits include the BBC-HBO mini-series Rome. 'He brings a different look to The Punisher and appears as if he came to life from a Tim Bradstreet cover,' Hurd says, referring to one of the most hard-edged cover artists ever to work on The Punisher series.

While the first film was set in Florida at the behest of production company Artisan, the sequel is set in New York and shot in Montreal last year. Hurd respects the mythology of the characters and is mindful of fan opinion, but she has previously warned of the dangers of becoming a slave to the message boards. 'There can be several iterations of a character and you even get different ink artists working on different comic-book issues, so you go with what the creative team responds to and once you start you can't second guess yourself.'

Platinum's Rosenberg believes one of the keys to success is to oversee a broad range of properties that can appeal to different tastes.

To complement its stable of original material, Platinum owns US libraries and European publishing houses including France's Hexagon and Italy's Sergio Bonelli Editore, with its celebrated Dylan Dog horror imprint (Platinum Studios and Ashok Amritraj's Hyde Park Entertainment are producing a live-action version of Dylan Dog, to be called Dead Of Night in the US and Dylan Dog elsewhere).

The studios have wasted little time mining opportunities (see sidebar). Universal recently signed a deal to adapt properties from Dark Horse, whose stable has spawned 30 Days Of Night, The Mask, Mystery Men and the Hellboy films. Marvel has 5,000 characters in its library. 'It's an embarrassment of riches,' says Marvel's Broussard.

DC Comics' Noveck is likewise optimistic. 'We're going to make a Wonder Woman, a Flash, and so on. When' We don't know. But if we have learned anything from the early Batman films and Catwoman, it's about getting it right. It's as if we hold these characters in trust for the public and we don't want to screw up.'