There are a precious few performers who justify theater's existence, whose presences are so powerful that you cannot imagine why anyone would want to see anything but theater. Allen Johnson—writer, storyteller, boiler mechanic—is one of those people. His solo show Another You is a chain of dispatches from an inner typhoon of violence, sex, and longing. He is just back from a run at the Public Theater in New York and a three-city tour in Germany. Tonight is his only homecoming show. Sit in the front row. (On the Boards, 100 W Roy St, 217-9888. 8 pm, $15.)