The movie ”Karsten and Petra become best friends” opened in cinemas in 2013. The movie became a huge success and is now a part of most DVD shelves in families with children. The film is about Karsten and Petra, two 5 year olds who attend the samenursery. Along with Miss Rabbit and Lion Kid (two stuffed animals), they go out on adventures, but one day Miss Rabbit is gone missing.

The movie is based on Tor Åge Bringsværds known childrens books and is directed by Arne Lindtner Næss. Themusic is written by Lars Kilevold who also is the writer of songs as "Livet er for kjipt" and "Ute til lunsj"Monn-Iversen.