About half way through Adult Beginners, I began to wonder whether I wasn't watching a sitcom about a failed entrepreneur (Nick Kroll) whose reduced economic circumstances force him to move in with his sister and her husband (Rose Byrne and Bobby Cannavale). To make matters even more humiliating for Kroll's Jake, his sister and her husband live in the suburban house where Jake grew up. Stripped of his upscale Manhattan lifestyle, Jake is asked to earn his keep by taking care of the couple's young -- and sometimes difficult son. The comedy revolves around various additional indignities that are heaped on Jake, who suddenly finds himself sleeping on an air mattress in his old room. Cannavale gives what's becoming a familiar performance for him, the gruff but good-hearted guy who's a little wayward. As the pregnant Justine, Byrne splits the difference between comedy and drama, and Kroll -- perhaps best known for his work on Parks and Recreation -- alternately annoys and amuses in a comedy in which director Ross Katz focuses on two siblings who re-establish their childhood bond. The movie's title stems from the fact that neither Kroll nor Byrne's character ever learned to swim. At some point, Jake must leap into the pool of adult responsibility and also get his priorities straight. Fair enough, but when it comes to expanding the world of indie-oriented comedy, Adult Beginners seems to be treading water.