It's back to school for sisters and caterers Bernie and Libby Simmons when a killer decides to teach a PTA president a lesson...

When Rita Sullivan walks into A Little Taste of Heaven to hire Bernie and Libby to cater a PTA board meeting and supply cakes for an end-of-school-year gala, it's hard to believe she's the same nerdy wallflower they knew in high school. Rita's now an influencer and CEO of Lavish Lipsticks, a hot new cosmetics company. She's also the president of the Longely Junior High School PTA, where she's made a considerable number of enemies. When the sisters go to drop off the cakes, they find Rita lying on the floor with a knife in her chest. What's more, using her company's newest lipstick, Scarlet Shame, the killer has drawn a large red X across her body. Rita has been canceled.

The police zero in on Abby Roth, owner of the murder weapon, but her kids beg Libby and Bernie to clear their mom's name. The sisters soon discover a quorum of suspects with motives to kill Rita, ranging from stolen cosmetics formulas and blackmail to broken marriages and property feuds. Figuring out which of them served Rita her just desserts will be anything but a piece of cake . . .