On the day they are born, every Swift child is brought before the sacred Family Dictionary. They are given a name—and a definition. A definition everyone assumes they will grow up to match. 

The reunion is only a day away and Shenanigan, troublemaker and mischief enthusiast, has been rattling around the grand old Swift House, plotting future crimes and planning the hunt for Grand-Uncle Vile’s long-lost treasure. She's excited to finally meet her rogue’s gallery of relatives—until one of them gives Aunt Schadenfreude a deadly shove down the stairs.

With some help from her sisters and their newly befriended cousin Erf, can Shenanigan catch the killer? And in a world where definitions are so important, how will she define herself?