The Mastermind is the unseen host and antagonist in the limited-run series, 13: Fear Is Real. He invited 13 real-life people to his game. He added the elements from horror movies to his game.
Each time he made rituals for the contestants. Each time two contestants would lose the ritual and would be sent to the execution ceremony where one will live and the other will be "killed off". In addition, the Mastermind introduced the Death Box, a tool in which one contestant would use to eliminate three fellow contestants. If one contestant accuses the other of having the Death Box and is correct, then the person who has the Death Box would be sent to the execution ceremony. On the other hand, if the accuser is wrong, that person would be sent to the execution ceremony him/herself.
All of those that were "killed off" were "proxy victims".
- Lauren Harris: She "suffocated from being buried alive".
- Laura Paul: Her face was "eaten alive by rats".
- Ryan Norys: He was "crushed" by a falling tree taken down by a chainsaw.
- Kelly Marquardt: She was chained and "burned alive" at the stake.
- Rodney Craft: He got "sliced in half" by a pendulum.
- Leah Lucas: She "drowned" in the flooding bathroom.
- Melyssa Nocar: She was "crushed to death" in the trunk of a car
- Nasser Goins: He was "killed" by a minion wielding an axe.
- Steffinie Phrommany: She was "killed off" by Rodney.
- Cody Minshew: He was "killed off" by Erica.
- Adam Wood: He was "killed off" by Erica.
- Erica Johnson: She was "killed off" by Nasser in the first part of the final execution ceremony.
Since the show didn't pick up for a second season, the Mastermind's identity is never revealed.