'The Nut Job' stars open up about their film

The Nut Job
The Nut Job

Not all stars can boast that they 'became' squirrels for a role -- but now, Will Arnett and Katherine Heigl have that distinct honor.

They're starring in 'The Nut Job,' a film based on director Peter Lepeniotis' 2005 short animation 'Surly Squirrel.'

Arnett says that being a voice actor can be tricky because there are a 'lot of little things that you don't think about that you take for granted when you're doing a live action movie. Questions you have to ask like 'how far am I from this person in this scene, how big is the shot you see them in?' You have to create that sense of space.'

Heigl says she thought it would be great to be in an animated movie that she could watch with her kids. 'I just thought one night it would be really fun to surprise my kids with a movie that I was actually a part of, that my voice is in.'

For Arnett, the film is all about redemption, and the idea that there's 'always time to do the right thing' ... and eat some nuts in the process.

'The Nut Job' will be released in theaters on January 17th.