When movie mogul Mandrake Masterfiend, producer of the schlockiest horror movies in history, invites some of Hollywood's craziest characters to his birthday party, the evening's a killer--literally. That's because he also invites Rona LaMona, the most vicious gossip columnist in the business who writes weekly under the title "The Poisoned Pen," to stir up the pot a bit. Though the actors, designers, and directors of some of Masterfiend's greatest successes enthusiastically reenact some great scenes from his movies, they suddenly find themselves playing suspects when Rona bites off a little more than she can chew of her poisoned pen and dies. Luckily the actress who portrays "Sabrina Slade--Girl Detective" on a weekly television show is on hand to take charge. Sabrina interviews the suspects and begins to gather evidence but isn't quick enough to stop the killer from killing a second, then a third time! There's nonstop action and laughs as Sabrina tricks the killer so truth, justice and the American way can prevail!