Shawn and Gus attend a Civil War reenactment rehearsal for the sheer pleasure of watching Lassiter have a nervous breakdown as he runs it.

When a scripted death turns real they end up donning uniforms themselves in order to find the murderer and perhaps prevent another.

Henry's old captain believes he's solved a murder, but his Alzheimer's has caused him to forget the most important details: the crime, and who committed it.

Henry calls in Shawn and Gus who find themselves investigating a murder that happened decades ago and only the faulty memory of the retired officer gives them any hope of closing the case.

When Lassiter doubts his own crime-solving ability, Shawn tries to boost his confidence by helping him solve an astronomer's mysterious death.

Lonely and bored, Shawn convinces Juliet to give him a shot with a case involving a missing tennis star, but first he has to spring an unwilling Gus from a corporate retreat.

Juliet asks Shawn and Gus for assistance on her undercover assignment. They're only too glad to help, since it involves sorority sisters. Unfortunately, what's supposed to be an easy case turns out to have ties to their past and may endanger Juliet.

Meanwhile, Lassiter locks horns with the oldest rookie the departments has ever trained.