The new comedy See How They Run is a whodunit for people who really like a whodunit. Set behind the scenes at a 1950s production of Agatha Christie's The Mousetrap, the film is a murder mystery with a big cast that includes Sam Rockwell, Saoirse Ronan, David Oyelowo, Ruth Wilson, and Adrien Brody. And it's an entertaining send-up that takes some very meta swings at the very idea of a murder mystery.