LOS ANGELES - Almost a decade after his sci-fi bomb "Solaris," George Clooney is returning to space in "Gravity," a 3D thriller that has become a game of musical chairs for actors.

The project revolves around a female astronaut (Sandra Bullock) trying to make it to Earth after a disaster in space. Clooney will play her colleague.

The initial pairing for the Alfonso Cuaron-directed project was to have been Angelina Jolie and Robert Downey Jr. Then came a protracted series of reversals that saw Jolie leave and come back, while actresses Marion Cotillard, Scarlett Johansson, Blake Lively and Natalie Portman were involved with the movie to varying degrees, all within the last eight months.

Downey stuck with the project throughout the various casting changes but in mid-November, just as things looked set with Bullock, he bailed.

Warner Bros., partnering on the film with financier Legendary Pictures, considered scrapping the project but conducted a Hail Mary search for the male lead who, while doesn't carry the movie, is still pivotal in the first act.

The studio is eyeing a spring start of production after Clooney directs Ryan Gosling and Paul Giamatti in the political drama "Ides of March."

His 2002 film "Solaris," in which he played a psychologist investigating mysterious behavior on a space station, earned just $15 million at the North American box office.