As directed by Chicago improv veteran Susan Messing–known for her take-no-prisoners approach–the late-night, long-form Trois is edgy and challenging. Together Katie Caussin, Lori McClain, and Alida Vitas push the boundaries of comedy: one night their characters included a religious woman who has sex with a Virgin Mary endowed like a male; a lecherous President Bush, who tries to seduce his new Secret Service agent, Tipper Gore; and two men ogling a plus-size stripper.

All three women are smart, skilled improvisers, and their sketches, based on a single audience suggestion, flow together with few blackouts, broken up only by occasional monologues. The performers mesh well: Vitas is the physical comedian, McClain adds depth, and Caussin is wildly funny. Too often, however, it seems scenes are outrageous simply for shock effect, and though they’re entertaining, they’re also cold. But since improv productions evolve, it’s likely Trois will be a powerhouse by the end of its run.

Panties Happy!, by contrast, offers humor with heart. Dina Facklis, Nicky Margolis, and understudy Rich Sohn (Angela Forfia was out the night I attended) have honed their chemistry on an ImprovOlympic team. Here they take a single audience suggestion and create a series of interlocking sketches so grounded in character they become believable, often poignant and always blazingly funny. An English couple chat happily in the ashes of their home right after it burns down. A woman is raped by a wood nymph. A little girl believes that her dolls talk–and that they’re saying bad things about her mother. There are a few unsuccessful monologues, but the only real wrong note is struck when the characters step out of scenes to explain what’s written on another character’s panties (“Take these if you need them”). Supposedly witty summations of the panties wearer or the scene, these lines aren’t clever, and the interruptions are annoying. But the rest of the show is fresh and funny.