A Real Rain - S1-E17
Character mistake: In the initial meeting at FBI headquarters, the agents mention the Zodiac killer. Gideon says about him "Yeah, and he killed for 30 years without being caught." In actuality, the Zodiac's known victims were killed between 1966 and 1970. In letters to the public, Zodiac claimed responsibility for several other murders (most of which were solved without being attributed to Zodiac), but no later than 1974. Gideon's statement was off by at least 22 years.
A Real Rain - S1-E17
Continuity mistake: When Gideon puts on a glove to examine the flint blade from the fourth victim's head, the glove snaps and breaks. In the next shot, more close up, Gideon's glove is not broken.
A Real Rain - S1-E17
Continuity mistake: At the end when the FBI is going to the apartment where the killer is holding the hostages, Gideon puts on a bulletproof vest while standing next to the car talking to the cop and a second later while he's walking toward the building he puts the vest on again.
A Real Rain - S1-E17
Visible crew/equipment: In the suspect's apartment by the boxes, there is a green tape marker at Reid's feet. (00:35:00)
A Real Rain - S1-E17
Visible crew/equipment: When talking about the cop killer victim in the police station, an orange tape marker can be seen on the floor. (00:19:20)
A Real Rain - S1-E17
Factual error: When BAU walks up the stairs on the way into the courthouse the first time, the John Ferraro building in Los Angeles is visible in the background. They are walking up the stairs toward Los Angeles City Hall. The episode takes place in New York.
Chosen answer: Back in Target Rich, a hitman named Giuseppe Montolo dies whilst being interrogated by Derek. The men who abducted Derek were hired by his father, Chazz, who seems to blame Derek for his son's death. It's explained further in A Beautiful Disaster.
Annabel Keeley