The third Marx Brothers movie and the first that wasn’t based on one of their stage productions, Monkey Business allows for a welcome bit of personal space between the audience and the comedians’ antics. Most of the picture takes place on a luxury cruise liner – on which Groucho, Chico, Harpo and Zeppo are stowaways – and the setting makes for a wonderful comic playground. Racing up and down decks and in and out of cabins, the brothers exhibit a more sophisticated sense of staging and interplay than they did in something like Animal Crackers (at times they even recall the comic intricacy of Keaton and Chaplin). But then the movie opens up too much. For their final act, the troupe moves from the ship to a familiar house party, where dull routine sets in. I’d even argue that the climax – a drawn-out boxing match between Zeppo and a hastily concocted villain – features the uncomfortable sight of the normally effortless Groucho straining to fill the dead air with laughs.