Brad Pitt is known for being one of the more mercurial superstars in Hollywood.  One day he's on a project, the next day he's mysteriously out.  Over the years, Pitt has flirted with two Darren Aronofsky projects.  He was originally set to star in the filmmakers Sci-Fi drama "The Fountain," but when the picture was reconfigured at a lower cost, Pitt dropped out.  More recently, the duo were attached to the boxing drama "The Fighter."  Both men stepped away from that Paramount Picture and David O. Russell, Christian Bale and Mark Wahlberg filled the void.  Now, the two intriguing talents are tempting audiences again with the new thriller "The Tiger."

Based on a new nonfiction book by John Valliant, "The Tiger: A True Story of Vengeance and Survival," the film will take place in Siberia where the tiger's habitant is being invaded by encroaching development.  Described as almost "supernatural" by Variety, its a fight that only a conservationist game warden can possibly win.  Pitt will produce and is considering playing the warden.

A former collaborator of Pitt's, "Babel's" Guillermo Arriaga, will adapt the novel for the big screen.

Pitt will next be seen in "The Tree of Life" and heard in DreamWorks Animations' "Megamind."  He's expected to begin shooting the long-delayed "Moneyball" sometime this summer.

Aronofsky is putting the finishing touches on his Fox Searchlight dramatic thriller "Black Swan."

Currently, there is no production timetable for "The Tiger." That leaves more than enough time for both Pitt and Aronofsky to move on to other projects and prove their union was never meant to be.