Poor actor-sleuth Charles Paris (So Much Blood, etc.) is now reduced to playing small roles in a provincial production of Macbeth--where his colleagues include a nervous director, a terribly earnest leading lady. . .and foul old character-actor Warnock Belvedere, a lazy egomaniac at rehearsals and a boozy, homosexual lecher backstage. It's no surprise, then, that Belvedere soon turns up dead--in the storeroom of the theater's bar, asphyxiated by leaking carbon-dioxide from a broken beer-pump line. Was this an alcoholic accident? Or elaborately arranged murder? Brett doesn't work very hard at providing Charles with plausibly motivated suspects. (The primary possibility is the dedicated Lady Macbeth, who wanted the rude old ham fired.) But if this is very much lesser Brett in the plot and detection departments, it's slightly above average in its show-biz comedy--with droll commentary on Charles' quick-change performance of multiple roles (an ever-increasing number) and a spot of uproarious slapstick during a matinee-for-schoolchildren.