In his best film, Chasing Amy, Kevin Smith wrote a line of dialogue that pegs the average comic-book reader as a sexually frustrated, underweight or overweight guy. That line gets at the core audience of Ivan Reitman's My Super Ex-Girlfriend, a comedy about men who fear women. The key figure for a film this silly and outrageous to work is the straight man, and although Luke Wilson is appealing, he is miscast. If nothing else, Wilson is a likable and low-key screen presence. For this character to work, he has to be somewhat unlikable, and Reitman seems afraid to let the audience feel that way toward him. This is even more obvious by giving him an obnoxious best friend, played by the underappreciated Rainn Wilson. All of this throws the balance of the film off when Wilson's ex, a very game Uma Thurman, starts her fits of raging jealousy that include throwing a live shark at him while he is in bed with another woman (Anna Farris). The tonal problems are compounded by the fact that Wilson and Farris are exceedingly appealing in their scenes together, and by the warmth and charm between Thurman and Wilson before their relationship sours. One wishes the film would chuck the superhero storyline altogether and let these three talented performers play in a conventional romantic comedy not saddled with the superhero story. My Super Ex-Girlfriend is a jumbled mess, sections of which work quite well, some of which dies on the screen. Despite the elements that work, the filmmakers can't maintain the film's tone, and end up simultaneously patronizing and pandering to the underweight and overweight guys they think they want to reach.