Dex is hired by a wealthy man to search for a woman whom he recently met, but she quickly learns that the task is not as simple as it seems; Dex and Grey's history unfolds.
In hopes of becoming a certified private investigator, Dex seeks mentorship from veteran PI Artie Banks; Hoffman grows suspicious of Grey after evidence proves that he has a connection to a dead ex-con.
Dex faces off against Artie Banks to take down a wealthy real estate mogul named Randall Tapper. Meanwhile, Detective Cosgrove leads an investigation to find a prisoner on the loose named Wallace Kane.
Hoffman tries to find out where Kane is hiding without the knowledge of his captain. Grey does whatever he can to get free from the grasp of Kane. Dex has a very important meeting that could very well change her life.
When Dex's ex, a famous musician, comes to town for a performance, Dex must protect her from a stalker; Grey continues to receive the cold shoulder from Dex; Tookie and Lt. Cosgrove develop a new friendship.
Dex goes undercover after she is hired by a local politician to dig up dirt on his political opponent. Meanwhile, Grey and Liz's romance continues, and Dex celebrates a tense Friendsgiving at the Bad Alibi.
Dex is confronted with unresolved feelings from her past when she is hired by Sue Lynn to investigate a case with the widow of Dex's former flame. Meanwhile, Dex and Grey's friendship is put to the test by his new romance with Liz.
Dex goes undercover as a high school substitute teacher after an old classmate of hers enlists her help to find out who planted drugs on her daughter. Meanwhile, Dex and Liz's relationship gets too close for comfort.