Following the dramatic series finale of Celebrity Traitors, we speak to Dr Dante Kalise from the Department of Mathematics at Imperial College, as he unpicks the treacherous tactics used in the game. He explains how the Traitors used game theory to betray their way to the top, and how the Faithfuls tried to unmask them using strategic deduction – a mathematical deep-dive into the art of betrayal.
Spoilers for the final of Celebrity Traitors below.
What is your area of research?
I work on dynamic optimisation, which deals with optimal decision-making for processes that evolve in time. This ranges from how to optimise an aircraft flight path to minimise fuel, to understanding optimal strategies in many-player games.
Predictability vs Adaptability: How does sticking to a pure strategy (e.g. always voting based on gut instinct) make a player vulnerable in The Traitors?
Pure strategies are optimal in games where there’s no hidden information or simultaneous moves (like chess or tic-tac-toe). Pure strategies in The Traitors make you predictable and exploitable; if you always vote for “the quietest person,” Traitors learn this pattern, act loud and confident around you, and keep you alive as a useful tool who’ll consistently vote how they want.
Randomization as a Shield: In what ways can randomizing your decisions (a mixed strategy) help you avoid suspicion or detection?
Randomizing decisions prevents others from learning your pattern, so no one can predict or manipulate your vote. This helps you blend in with genuinely confused Faithfuls who scatter their votes unpredictably.
Strategic Shifts: Can you think of a moment in the game where a player clearly changed their strategy? What might have triggered that shift?
The most evident strategic shift, and certainly a catastrophic one, was Nick Mohammed’s final decision to conclude that Joe Marler was a traitor. This shift was likely triggered by Alan’s masterful deflection at the final Round Table, where he questioned Joe’s behavior and planted just enough doubt to break Nick’s confidence in their partnership. Nick and Joe would have won otherwise!
Consistency vs Deception: Is it ever beneficial to appear consistent even when you’re not? How might this play into others’ expectations?
Yes, appearing consistent while secretly varying your strategy can be powerful. If you publicly claim “I always trust my gut” but actually calculate strategically, others treat you as predictable while you maintain hidden flexibility. This exploits others’ pattern-recognition, and no one can prove you’re lying because gut feelings are subjective and unverifiable.
What tactics did Traitor Alan Carr use to win the game?
Alan won by using what in game theory is known as a “pooling equilibrium” strategy. By acting so obviously suspicious, he became indistinguishable from a nervous Faithful who was simply bad at the social game, causing everyone to dismiss him as harmless. By pooling his behavior with the “worst possible Faithful” rather than trying to signal innocence like most Traitors do, Alan made his guilt invisible.
Lastly, would you rather be a Traitor or a Faithful?
I think I’d rather be a calm Faithful like Nick, being a Traitor is a full-time job.
Watch Dr Dante Kalise explain how Alan Carr won on Instagram here.