In each round, the teams are presented with a lineup of people who all claim to have a particular unusual trait or skill (e.g. being able to hold their breath underwater for more than five minutes), but only one of them is telling the truth. The teams may ask questions of the lineup members in order to determine the truth-teller. At the end of the round, each team may make one guess as to which one is the "Odd One In," receiving one point for a correct choice. Where appropriate, the lineup members are invited to demonstrate their purported skill.
During the first series, the members in one section of the audience are given keypads on which to lock in their guesses as to the Odd One In. After the penultimate lineup has been played, the high scorer is invited to compete for a £5,000 cash prize by correctly spotting the final Odd One In, with help from the two teams and the rest of the audience.
The keypads and cash prize are eliminated for the second series. The final round is replaced with a "Familiar Faces" lineup, consisting of one or more members from each of the previous rounds; the teams must determine which is the Odd One in as before.
Episodes
The coloured backgrounds denote the result of each of the shows:
Line Ups Who has the fake beard? ― Who is part of a roller skating act? ― Which is the record breaking Glider pilot? ― Who married a pineapple? ― Which is the real nun? ― Who is doing a handstand?
Line Ups Who is the hairiest man? ― Who is the real Frenchman? ― Who is the real hypnotist? ― Who is doing football keepie-uppies? ― Who is lifting real weights?
Line Ups Who is wearing a wig? ― Who is the real Russian? ― Who is the real stunts performer? ― Who is the real winner of Lithuania's Got Talent? ― Who is doing the Caribbean dance?
Line Ups Who is the real hula-hoop dancer? ― Who is the real London geezer? ― What animal can go on a skateboard? ― Who is part of a balancing act? ― Who is the professional whistler?
Line Ups Who is the real riverdancer? ― Who is the real contortionist? ― Who is the real Mexican? ― Who is getting shocked? ― Who can do a backflip from a wall? ― Who is the professional hairdresser?
Line Ups Who has a fake moustache? ― Who can pull a chariot with their teeth? ― Who is the real woman that a man married? ― Who is the musical genius? ― Who is the professional escapologist? ― Which pair of legs belong to a woman?
Line Ups Who holds the current Guinness World Record for having stretchy skin? ― Who is the sibling of a celebrity? ― Who is the current champion for eating stingy nettles? ― Which Coronation Street star is having their feet licked by a dog? ― Who is actually playing the electric guitar?
Line Ups Who is the real tapdancer? ― Which contestant changed their name by deed poll to Captain Fantastic faster than Superman Spider-Man Batman Wolverine Hulk and the Flash combined? ― Which couple have been married for over fifty years? ― Who of the line up is fluent in Mandarin? ― Who is actually beatboxing?
Line Ups Who is really Welsh? – Who injured themselves while doing something with a sausage? – Who's the real Karate champion? – Who has a famous voice? and for the familiar faces round – Who won a TV talent contest in Spain?
Line Ups Who is the real Italian? – Who can walk a tightrope? – Who's a genuine royal? – Who is known as the 'Human Windmill'? and for the familiar faces round – Who is the real conga player in a Brazilian band?
Line Ups Who is the real sport stacker? – Who eats something unusual as part of their job? – Who is the real Scotsman? – Who has had a silent role in a well-known TV programme? and for the familiar faces round – Who can do a handstand and shoot an arrow with their feet?
Line Ups Who is the real player of street basketball? – Who can sing like a woman? – Who is the real country bumpkin? – Who is a super-citizen? and for the familiar faces round – Who is the real fast player of a violin?
Line Ups Who is the real Australian? – Who is the real cheerleader? – Who holds the Guinness World Record for stuffing 400 drinking straws in their mouth? – Who is the real Bollywood actor? and for the familiar faces round – Who can play the trombone?
Line Ups Who is the real American? – Who can hold their breath underwater for five minutes? – Who can balance a table (that someone is to sit on) with their mouth? – Who has fake sideburns? and for the familiar faces round – Who can jump on a pogo-stick?
Line Ups Who is the real Greek? – Who has a fake tattoo? – Who can lift a basket with their ears? – Who has a fake mullet? and for the familiar faces round – Who is part of a knife-throwing double act?
Who has a voice of an angel? – Who is the real pretentious Santa? – Which is the fake Christmas tradition? – Which is the real couple? and for the familiar faces round – Who can play the tuba?
International versions
The format was exported in Italy, Ukraine and Vietnam.
