Scarlett Johansson is in talks to reunite with Robert Downey Jr on director Alfonso ‘Children of Men’ Cauron’s long-gestating science-fiction film, “Gravity”.

Warner Bros and Legendary Pictures are behind the pic, which is said to be a survival thriller that follows a woman as she attempts to make her way back to earth after a satellite crash sets off a chain reaction of further crashes.

Johansson, who recently worked with Downey on “Iron Man 2″, is stepping in for Angelina Jolie. Jolie was attached to the picture when it was set up at Universal, but left the picture “when she learned she’d have to share screen time with a leading man” says The New York Daily News.

The film will shoot in London shortly.