Abbott and Costello performed this bit in several different forms with trigger words "Niagara Falls," "Pokomoko" and, in one instance, both "Susquehanna Hat Company" and "Bagel Street." Lucille Ball performed it with a clown in an episode of I Love Lucy
with the trigger word "Martha." The Three Stooges played it as "Niagara Falls" using their trademark slaps and pokes and included a final scene where the best friend arrives and claims that HE slowly turned and attacked the stranger, with the end result that both the stranger and the best friend pummel the innocent man.
David - Mesa, AZ, for above 2