Callaham comes to the project after having worked on the script for Godzilla earlier this year. His script "Barrow" would become The Expendables, and he was also chosen by Marvel to do a production rewrite on the upcoming Ant-Man. Deadline says it is Callaham's work on the dark yet comedic Jackpot, a Focus Features film based on a story by crime writer Jo Nesbo, that landed him the Zombieland 2 gig from Sony Pictures.

The original Zombieland had a unique combination of zombie violence and quirky humor going for it, no doubt a special quality Sony is looking to bring back for the sequel with the Callaham hire. Zombieland in 2009 made more than $100 million at the worldwide box office for a production budget of only $23.6 million. With those numbers, it's surprising a sequel wasn't fast-tracked much sooner, especially given the massive ongoing success of other zombie properties like AMC's The Walking Dead and news that popular zombie video game Dead Island will be getting a film adaptation.

There is still a lot of uncertainty surrounding the project, however. As the script isn't done, it is unclear if any of the stars from the original Zombieland will be returning for the sequel. Almost every star in the film has only grown in popularity since 2009: Jesse Eisenberg will be Lex Luthor in Batman v. Superman: Dawn of Justice, Emma Stone starred as Gwen Stacy in The Amazing Spider-Man and The Amazing Spider-Man 2 and Woody Harrelson made headlines for his performance next to Matthew McConaughey in HBO's True Detective. No doubt the stars would be asking for money this second time around more than they did for the first film, something Sony will have to consider as it decides whether or not to bring back characters from the first film or introduce new characters set in the same world. Just don't count on Bill Murray making another cameo appearance.