Not since the legendary Richard Burton and Elizabeth Taylor has a couple had a more tempestous relationship than Christopher and Mark. One minute they're snogging in the store room and the next they're screaming (well, Mark is) at each other. Here are their five biggest tiffs:
Christopher was a little upset about being treated like a child by Mark and the other housemates.Well, he is one year younger than Mark.
Mark was flabbergasted that he wasn't the first person in human history to have genuine psychic powers and he took his frustrations out on Christopher.
Things went up a notch when Helen told Mark that Christopher had been lying to him about his psychic accuracy. He really should have seen it coming.
Mark was upset when Christopher picked Helen as the most loyal housemate. Amazingly, Mark's abilities failed him yet again as he was very surprised by Christopher's choice.
After another big row fuelled by some wine, Christopher almost called time on his relationship with Mark.
But they have had some good times, like this sweet moment captured in lovely little gif:
Will Mistopher last beyond the BB House? Will they even last until tomorrow? Stay with us to find out.