Below Zero.

When Jack (Edward Furlong) is in danger of missing a deadline, his manager orders him to take whatever measures are needed to complete his screenplay. Jack locks himself in a slaughterhouse freezer but discovers that his inner demons are keeping him company. Despite the cold, Jack's imagination is red-hot as he concocts the story of Frank (Furlong), a tow truck driver who's locked in a fridge with the dying victim of a serial killer.