LOS ANGELES  - Joaquin Phoenix is no longer in talks to play Abraham Lincoln's mentor in "Abraham Lincoln: Vampire Hunter", movie insiders said on Thursday.

Instead, 20th Century Fox is in final negotiations with English actor Dominic Cooper ("Mamma Mia!") in the big screen adaptation of the period vampire novel by Seth Grahame-Smith.

Cooper will star opposite Benjamin Walker, who landed the coveted role of President Abraham Lincoln last month, as director Timur Bekmambetov moves to cast lesser-known stars, versus big names.

Cooper will play Henry Sturges, who mentors and trains Lincoln in the ways of vampire hunting.

Last month, Cooper made waves at the Sundance Film Festival for his dual roles in the indie film "The Devil's Double", in which he plays both Saddam Hussein and the late Iraqi leader's double.

This summer, Cooper has a supporting role in Marvel Studios and Paramount's "Captain America: The First Avenger."

The cast of "Vampire Hunter" is beginning to round out.

In talks to play the role of Lincoln's best friend is Anthony Mackie, another young actor. His film credits include last year's best picture Oscar winner "The Hurt Locker" as well as "We Are Marshall" and "Eagle Eye".

Although the studio declined comment on possible female leads, two names being mentioned are Mary Elizabeth Winstead ("Scott Pilgrim vs. The World") and Australian actress Robin McLeavy.

"Abraham Lincoln: Vampire Hunter" is Bekmambetov's first movie since the 2008 hit "Wanted", and tells the story of how Lincoln crushes vampires during the U.S. Civil War.