Every summer for the past ten years, six awe-struck bakers have descended on the grounds of Grafton, the leafy and imposing Vermont estate that is not only the filming site for “Bake Week” but also the childhood home of the show’s famous host, celebrated baker Betsy Martin. The author of numerous best-selling cookbooks and hailed as “America’s Grandmother,” Betsy Martin isn’t as warm off-screen as on, although no one needs to know that but her. She has always demanded perfection, and gotten it with a smile, but this year something is off. Things go awry as the baking competition begins. At first, it’s merely sabotage—sugar replaced with salt, a burner turned too high—but when a body is discovered, everyone is a suspect.