Gracie Allen breaks the Philo Phormula in a number of ways. First is its title: this is the only book in the series to modify “Murder Case” with more than one word, much less with the name of a character. And then there’s that character: Gracie Allen was a very real, much-loved comedienne in the 1930s, famous for her double act with George Burns, and in fact the plot revolves around her. Gracie’s centrality is no accident: Van Dine wrote the story as a vehicle for Allen, and actually created the novel only after the film had come out. So do all these departures pay off? We’d be lying if we said that Gracie hits every single mark, but Van Dine does a surprisingly entertaining job of translating Ms. Allen’s delicious Ditzy Blonde persona to the page, and she makes a charming foil for Philo’s evergreen erudition.