Roger Ebert wrote that he "enjoyed "The Butterfly Effect", up to a point" and that the "plot provides a showcase for acting talent, since the actors have to play characters who go through wild swings." However, Ebert said that the scientific notion of the butterfly effect is used inconsistently: Evan's changes should have wider reverberations. Sean Axmaker of the "Seattle Post-Intelligencer" called it a "metaphysical mess", criticizing the film's mechanics for being "fuzzy at best and just plain sloppy the rest of the time". Mike Clark of "USA Today" also gave the film a negative review, stating, "Normally, such a premise comes off as either intriguing or silly, but the morbid subplots (there's prison sex, too) prevent "Effect" from becoming the unintentional howler it might otherwise be." Additionally, Ty Burr of "The Boston Globe" went as far as saying, "whatever train-wreck pleasures you might locate here are spoiled by the vile acts the characters commit."