When Indigo Tea Shop owner Theodosia Browning is invited by Doreen Briggs, one of Charleston's most prominent hostesses, to a Rat Tea, she is understandably intrigued. As servers dressed in rodent costumes and wearing white gloves offer elegant finger sandwiches and fine teas, Theo learns these parties date back to early twentieth-century Charleston to promote better public health.

But this party goes from odd to chaotic when a fire starts at one of the tables and Doreen's entrepreneur husband suddenly goes into convulsions and drops dead. Has his favorite orange pekoe tea been poisoned? Theo smells a rat. And as she reviews the guest list for suspects, she soon finds herself drawn into in a dangerous game of cat and mouse...