Exclusive: Ewan McGregor, Dennis Quaid & Michael Douglas (& More) Join Steven Soderbergh's 'Knockout'

When the action spy picture "Knockout" was first announced a few months ago, director Steven Soderbergh promised that the lead star, non-actress/ mixed martial arts champion Gina Carano would be surrounded by a name-recognizable cast of supporting talent and he wasn't kidding.

Sources close to the project have confirmed to us that the principal cast members supporting Carano include Michael Fassbender ("Inglourious Basterds," "Hunger"), Ewan McGregor, Dennis Quaid and Michael Douglas.

However, it looks like the original concept, — a girl from the wrong side of the tracks who is given a second chance to use her skills for constructive purposes — having gone through the gestation/inception stage was eventually rethought and cast aside (both filmmaker and writer felt that it had "been done").

Ultimately, "Knockout" is now more of a revenge action-spy thriller. Essentially it's hell hath no fury like a woman scorned and especially one who kicks serious ass. Double crossed by someone on her own team, Mallory Kane (Carano)— a black ops super soldier — seeks to uncover who has set her up to take the fall for a job that goes bad and involves a murder.

The male actors are all part of Carano's special forces team. Douglas plays a government figure not unlike Chris Cooper or Brian Cox from the 'Bourne' movies. Fassbender and one other actor who has yet to sign-on officially (we've been asked not to say who because it's not 100% confirmed, but the actor is male and a fairly big name; though it's possible scheduling conflicts may prevent him from participating) play members of her commando spy unit, and one of these two plays the central antagonist that betrays Carano's character (this is still being kept under wraps for now). McGregor's role is that of the owner/guy who runs a Blackwater private military company-type group that the female fighting champion is a part of (and apparently many of the males take a beating at the hands of Carano).

And as noted, Carano's Kane character is no longer a girl from the "wrong side of the tracks," she now has a solid background and was raised around military honor and academia. She leaves the military to go to work for a Blackwater-esque company to make better money and then is eventually betrayed by one of her teammates.

Both Douglas and Quaid have worked with Soderbergh before in his Academy Award-winning 2000 film, "Traffic" and Douglas is set to star in the filmmaker's "Liberace" film if that happens according to plan this summer. Fassbender is the quickly rising, in-demand actor that everyone wants to work with (Tarantino, et. al) and the director is certainly one of those people — Fassbender's role was written with the actor in mind.

And Soderbergh has been circling McGregor for some time now. The "Trainspotting" actor was originally pegged to have a role in the 'Ocean's' films, but his commitments to Lucas' "Star Wars" prequels unfortunately precluded his participation.

"Knockout" — it's still officially a working title, but now we're told that people are warming up to the name and that it might eventually stick — was written by Lem Dobbs, the screenwriter behind Soderbergh's "Kafka" and "The Limey" also well-known for his contentious (and hilariously candid) DVD-commentary arguments with the director ("The Limey" commentary is like two friends with the gloves off and an amusing must-listen).

The director has previously said the film will take elements from "La Femme Nikita," the 'Bourne' films, the Bond film "From Russia With Love" and John Boorman's 1967 crime film "Point Blank," starring Lee Marvin (which is known as the slightly arty, thinking man's, tough guy picture). But he's also noted that the action will be distinctly different than the Greengrass vibe evinced in his 'Bourne' films. As reported last year, David Holmes, the composer behind Soderbergh's "Oceans 11-13" series, not to mention the brisk and funky "Out Of Sight" film, will be writing the score.

Soderbergh's deal for "Knockout" through Relativity Media and Lionsgate is a typically unique one for the adventurous filmmaker. He will be paid no upfront fee for directing the film, but eventually will retain full ownership of the film once its released. It's a bold and unprecedented move. Having just finished up his media-saturation play "Tot Mom" in Australia, Soderbergh is now in New Mexico doing scouting for his February production start date expected to shoot there, Ireland and Turkey among other possible locations.

Carano has been training in L.A. for two months and test fight footage has already been shot (she's already accidentally knocked out one stunt coordinator in practice sessions... no, really). Lionsgate is eyeing an August release. Producers on the project include Relativity Media's Ryan Kavanaugh, Soderbergh's longtime cohort Gregory Jacobs, and Tucker Tooley as an executive producer.

And while THR doesn't link to us, we're not above linking those that expand on things no matter what and they have a few more additional details on the characters.