A witty and fast-paced mystery by Janet Evanovich and the twenty-first installment in the beloved Stephanie Plum series. The novel follows New Jersey bounty hunter Stephanie Plum as she investigates the disappearance of Jimmy Poletti, a local gang leader who has vanished after skipping bail.

Stephanie's search takes an unexpected turn when a mysterious stranger claiming to be an undercover government agent arrives, insisting that Jimmy is connected to a dangerous terrorist plot. As bodies begin to pile up and the line between truth and deception blurs, Stephanie must determine who can be trusted while avoiding becoming the killer's next target.

Complicating matters are Stephanie's ongoing romantic entanglements with the dependable cop Joe Morelli and the enigmatic security expert Ranger, along with the usual chaos brought by her eccentric family and the ever-hilarious Lula.

Packed with laugh-out-loud moments, quirky characters, action, and suspense, Top Secret Twenty-One delivers another entertaining adventure in one of the most popular cozy crime series.