The Up in the Air director has teamed up with bosses at DreamWorks Animation to write and direct the film, which tells the story of a one-of-a-kind imaginary friend called Beekle who sets off on a journey in search of a best friend.

Written and illustrated by Dan Santat, The Adventures of Beekle: The Unimaginary Friend is the 2015 recipient of the Caldecott Medal, awarded annually to the most distinguished American picture book for children.

Reitman credits his eight-year-old daughter for inspiring him to tackle the project, saying, "I was book shopping with my daughter, when a little tooth-shaped character in a paper crown stole our hearts.

"I'm particularly proud to be working with DreamWorks Animation, makers of Kung Fu Panda, the first film my daughter ever saw on the big screen."