1. North-West and Northern Ireland Heat

The first 12 contestants face a quickfire round where they must spot the missing letters from the months of the year and a memory game where pairs must memorise the positions of ice cream tubs, toppings and cones.

3. South-West and Wales Heat

The next 12 contestants including “Sherlock” the pharmacist, a nanny who feels underestimated, and student Rosie face a fresh set of challenges based on the games Mensa use to measure IQ. The tasks include code breaking, lexical perplexity, and a particularly complex cipher involving a landline phone — something the youngest contestant, Rosie, struggles with for reasons beyond the difficulty of the puzzle itself. By the end of the episode, only three contestants will earn a coveted place in the Oxford finals.

4. South-East Heat

In the final heat, 12 contestants are put through a series of mind-bending challenges, hoping to claim one of the final three spots in the competition. With Alan Carr and Susie Dent hosting, they’ll face a physical anagram grid, a twist on Guess Who? featuring pictures of cats and dogs in regalia, and a challenging clock puzzle. Only three will advance to the finals.

5. The Semi-Final

The final 12 players are faced with a high-pressure quickfire round, where they must solve a complex maths game to work their way out of a maze. After some surprising drop-outs, the remaining top eight players face each other in a mind-bending memory game based on the periodic table, for a place in the final four.

6. The Final

Alan Carr and Susie Dent host the grand final. The four remaining contestants must place famous geniuses correctly on a giant board, before two are chosen to face the final challenge - a nail-biting second round of fluid reasoning and memory games.