I saw a taping of the UK BBC2 show, and here's what I can remember from the episode:
Contestants and their common "theme" are introduced. Let's say it's "I shared an apartement with someone famous".
Round one: audience members ask 2-3 questions of each of the six panelists.* Audience members then vote out who they THINK is the biggest liar. Highest vote IS the weakest truthteller.
Round two: five remaining players quiz each other, in an attempt to sabotage each other. Audience votes, eliminates.
Round three: four remaining players are questioned in a similar manner as round one. Audience votes, eliminates.
Round four: three remaining players each get to question each other (thus six questions). More voting.
Round five: two remaining face off: they each of thirty seconds to "say their piece", trying to convince the audience that they are the truthteller.
Then all is revealed... if the audience left the one truthteller, they split 10,000 pounds (50 quid each - not bad if you're Canadian like me). If not, the person that they left wins 10,000 pounds.
And that's that! I'm sure my good friend, Brig Bother, will contribute comments if I've missed something, as he was there at the taping with me.
Cheers,
Ryan
*I was on camera asking the first question! What a riot!