Peter MacNicol returns as a regular cast member. Colby is being interrogated by a man named Agent Kirkland, who passes him a handcuff key and gives him escape instructions. Don and his team get information about and from Colby and must figure out if that information is reliable then realizes that everything about Colby being a double agent may not be what it seems.
In this episode, it is discovered that someone has stolen, recreated and sold several copies of an extremely rare comic book. Christopher Lloyd plays the original creator of the comic book, who no longer benefits from his past creations. Having thought that his comics wouldn't be worth much in the future, he either lost or sold his entire collection and regrets it now that he and his wife live on very little. His young friend and fellow comics artist, played by Ben Feldman, publicly humiliates the rich man who owned the original before it was stolen.
A.U.S.A. Robin Brooks is back in town, and her involvement in Don's case brings back memories as they try to keep witnesses alive. Meanwhile, David attempts to bond with a young man who's in the chief suspect's thrall.
The murder of a rapper puts Charlie to work analyzing the mathematics of the music business in the same week that Amita's parents come to town, and Megan has asked for a week off without discussing it with Don.
When one of Charlie's friends, a scientist at the university, is arrested for terrorist activities, it puts him at philosophical odds with Don. And as he works to prove the man's innocence, his beliefs may jeopardize his career.