Exchange Mary Tyler Moore here for Marlo Thomas and you'd have the makings of a good two-part episode of "That Girl". As a feature film, however, "What's So Bad..." seems a little twee--and if the topic of a euphoric virus is supposed to be symbolic, any modern references towards getting high or living as we did in a previous era barely register (it's just too silly). Beatniks in Greenwich Village come across a mysterious Toucan who arrived in New York Harbor via a Greek freighter. Seems the bird spreads an extremely contagious "happiness bug," sending all the cynical, jaded drop-outs into the streets with their instruments and brooms. They dance on the rooftops to Frank DeVol's music, and it's breezy and corny, perfect for connoisseurs of '60s sitcoms. Unfortunately, a 'realistic' angle is dropped in, as mayor John McMartin and his cronies become fearful that all this lightheartedness will reduce sales in cigarettes and alcohol! They take refuge in a fallout shelter and work on getting an antibody which will turn everybody back into their old rotten selves. Forgotten Universal comedy has some big laughs--and gives us a marvelously gregarious George Peppard in the bargain!--but the handling is too flimsy for any sort of insight, and the second-half drags its feet. Supporting cast is filled with familiar faces (plus Thelma Ritter in a cameo), and the location shooting is very good, even if the cinematography is muddy and the direction flat. ** from ****