This interactive comedy whodunit opened in Boston 35 years ago and has been running there ever since. After spawning 42 productions in 11 languages on six continents, it has finally arrived in New York at New World Stages. The play is loosely based upon a German story by Paul Portner. The current setting is a Hells Kitchen unisex hair salon whose two stylists are the flamboyantly gay Tony Whitcomb (Jordan Ahnquist) and blonde bimbo Barbara DeMarco (Kate Middleton). The customers include a salon regular, East Side society lady Mrs. Shubert (Lynne Wintersteller), and three first timers — Mike Thomas (Adam Gerber), Nick O’Brien (Patrick Noonan) and Eddie Lawrence (Jeremy Kushnier) — two of whom turn out to be cops. When Madame Czerny, the former concert pianist/landlady who lives upstairs is stabbed to death with a pair of scissors, the cops are convinced that the murderer is someone at the salon. They ask the suspects to reenact the events, inviting the audience to point out holes in their stories and eventually to vote on who the murderer is. Along the way there are many slapstick jokes, naughty innuendos and comic references to current public figures. Each performance varies depending upon the input of the audience. On the sparsely attended Monday evening I was there, the energy level was low. Perhaps with a larger, more enthusiastic audience, the material might come across as funnier. As it was, the jokes seemed forced and the actors seemed to be working hard. How this show has attracted audiences for over 35 years is the real mystery to me. Why TDF is lending its support is another question. The set by Will Cotton looks authentic. Bruce Jordan’s direction is indulgent. If you attend, get there a few minutes early because the onstage action starts before the curtain time. Running time; two hours including intermission.