UK Casino scam - what exactly happened?

[jay kay]

Saw this on the morning news .... 3 people caught scamming UK casino "poker" games (poker in this case being a player vs dealer poker variant, not the real thing)

http://www.thisislocallondon.co.uk/n...rio_jailed.php

They had a hidden cam watching the cards the players were dealt and somehow worked out what to bet from that .. but it looks like they didnt see the dealers cards - so what was their edge??

JK