Manny Tamayo’s new play for Factory Theater–a convoluted parody of 1970s horror films in which government-created humanoids steal people’s souls and contaminate their drinking water–is not only confused but bloated with unnecessary characters and dead scenes. Nick Digilio’s elemental staging creates traffic jams anytime more than 6 of his 25 cast members are onstage at once. But only a neophyte would expect theatrical cohesion from the impudent, vulgar, ingeniously adolescent Factory, known for raising bodily-function humor to giddy heights. When Tamayo focuses on the hyperbolically dysfunctional family at the play’s center, the result is the kind of bratty, whip-smart evisceration of middle-class propriety that’s given the Factory’s 14-year frat party its long, disarming run. –Justin Hayford a Through 12/16: Fri-Sat 8 PM, Sun 7 PM, no show Fri 11/24, Prop Thtr, 3502-4 N. Elston, 866-811-4111, $20.