A team of three old university pals with a shared love of exotic foods and fine dining pit their wits against a trio of Ulstermen from the Northern Ireland Court Service.
The Wright family from Leeds pool their knowledge of IT, Electrical Engineering, and Mexican cinema to challenge the brainpower of the Urban Walkers, a team unified by their love of taking extended inner city hikes across various European capitals.
A doctor, a teacher, and an accountant with a shared passion for radio square up to a trio of professional taxomomists - three women who make companies more successful through their precise use of language.
Three stalwarts of the Camden music scene (including the man who discovered Blur) pit their wit and wisdom against a husband, wife, and pal who share a love of geocaching, the craze for treasure-hunting using GPS.
Three fantasy writers, captained by a man who has written for Doctor Who, lock horns with a trio of bridge players, each with post-grad qualifications from Oxford University.
Three friends who originally met through British Mensa pit their wits against a team drawn together by their love of TV blogs and forums.
Three dedicated hill walkers from Derbyshire face off against a family threesome of husband, wife, and brother-in-law.
Three men joined by their enthusiasm for real ale confront two maths graduates and a pharmacist who are a regular fixture at their local pool hall.
In the first of the quarter-finals, three old chums from university days who share a passion for fine dining take on the combined knowledge of three Oxford graduates with a love of bridge.
In the second quarter-final, the Wright family of mum, dad, and daughter return to pit their wits against a trio of committed bloggers who met on TV gossip forum sites.
In the third quarter-final, a doctor, a teacher, and an accountant with a unifying love of the radio return to challenge the brainpower of three Camden-based lynchpins of the British music industry.
In the last quarter-final, a family team featuring a patent lawyer, a graphic designer, and a business analyst return to the field of conflict to take their chances against a trio unified by their love of authentic cask-conditioned ales.
In the first semi-final, three lovers of luxurious wines and exotic dishes set aside their shared passion to address the challenge of the combined wits of the Wright family.
In the second semi-final, three lovers of authentic beer lock horns with the cunning of a team bound by their love of the airwaves.
In this play-off between semi-final losers, the Wright family combine their wits to take on the mental firepower of the Alesmen in a last battle for glory.
In the series finale, three committed gourmands set aside their love of fine foods to concentrate on the job in hand - battle for victory over the Radio Addicts, a team with the diverse combined knowledge of a doctor, a teacher, and an accountant.