he had vague memories : listening to a man who had once been a successful radio comic and then a variety star in tv ' , infant days telling a very long and very hilarious joke about incest between siamese twins ; seeing the woman in the harem pants and the sequined bra do a slow and sinuous striptease to some bumping-andgrinding music from the jukebox ( it seemed it had been david rose 's theme music from the stripper ) ; crossing the lobby as one of three , the other two men in evening dress that predated the twenties , all of them singing about the stiff patch on rosie o'grady 's knickers .