There's a lot about You Again that's instantly disposable, from its generic title to its bland leading lady to a story line that's as weightless as a sponge cake. But leave it to the old pros in the cast to prevent this from completely sinking into the abyss of immediately forgotten comedies. Kristen Bell, only fitfully succeeding in making an impression, plays Marni, who's shocked to learn that her brother (Jimmy Wolk) is marrying Joanna (Odette Yustman), the girl who made her life an endless hell back in high school. Everyone in Marni's family thinks Joanna is the greatest, so Marni makes it her mission to expose her as malicious and deceitful. For her part, Marni's mom (Jamie Lee Curtis) is aghast when she discovers that Joanna's aunt is a former school chum (Sigourney Weaver) with whom she had a falling-out decades ago on prom night. The Marni-Joanna clashes offer little that's new, so the fun is in watching those exquisite older actresses, Curtis and Weaver, square off against each other. Throw in the always-welcome Victor Garber as Curtis' husband, an amusing bit by Kristin Chenoweth as a dance instructor, and a cameo by a former Dallas star that almost made me fall out of my seat, and you may want to give You Again a chance. But only if Mean Girls isn't playing on cable.