The Ladykillers

The plot of an eccentric professor-turned-criminal-mastermind (Tom Hanks) to commit the massive heist of a New Orleans riverboat casino appears to be thwarted by the actions of Mrs. Munson, the seemingly-innocent little old landlady of the house that he and his three accomplices are staying in, and which is integral to their scheme (they want to dig a tunnel from it to where the casino's money is kept). So they decide that they need to remove her from the equation, but doing so might prove to be more difficult than they expect.