Peter takes the day off in an attempt to give Elizabeth an extraordinary birthday, complete with her parents. He leaves Diana in charge to find a missing Stradivarius with Sara and Neal, all under the prying eyes of Agent Kramer.
Peter is nervous since his in-laws are, by invitation visiting due to Elisabeth's birthday. Neal gets a case about a missing Stradivarius violin and Sara is leading the case. Diana's girlfriend has proposed, but Diana wants to push it.