JoBlo:
Gravity was a movie that almost didn't happen. At one point, every halfway decent actress in Hollywood was attached to star in the ambitious sci-fi project from Alfonso Cuaron. Angelina Jolie was originally set to star in the film with Robert Downey, Jr. Natalie Portman was her intiial replacement but she too walked. Scarlett Johansson, Blake Lively, Naomi Watts, Marion Cotillard, Carey Mulligan, Sienna Miller, Abbie Cornish, Rebecca Hall and Olivia Wilde all tested/auditioned for the role before producers finally settled on Sandra Bullock. (RDJ also walked and was replaced by George Clooney.) (Cinema, George Clooney, Gravity, Sandra Bullock)