Scarlett Johansson and Rachel McAdams are competing to star opposite Matt Damon in a new film.

The actor is to take the lead role in 'We Bought A Zoo' and director Cameron Crowe has reportedly drawn up a shortlist of actresses he wants to read for the main female part, including the two screen beauties.

Also being considered are Amy Adams and 'Scott Pilgrim Vs. The World' star Mary Elizabeth Winstead.

The film has been adapted from Benjamin Mee's book about the project he undertook with his family to restore the decrepit Dartmoor Zoological Park, saving many of the animals and repairing the house to live in.

The plans are going well until Benjamin's wife is diagnosed with fatal brain cancer.

Colin Ford and Thomas Haden Church are also signed up to appear in the film.

Shooting is scheduled to begin early next year, with the release date currently scheduled for 23 December 2011.