In 1994, Dumb & Dumber was one of the funniest movies I had ever seen. My ten-year-old self loved the dirty jokes, the characters’ charming stupidity, and the childishness of it all. As the Farrelly Brothers’ Dumb and Dumber To shows, that childishness—specifically the odd innocence of the characters—was key to making the original picture work. The sequel replaces that childishness with a mean-spirited attitude that turns obliviousness into narcissism and antics into attacks. There are still some laughs scattered about, but the heartlessness of the picture makes Dumb and Dumber To too nasty to be dumb fun.