It went wrong for mark with power trio he was two faced scuttling to Helen lying about his role and hanging Ashleigh and Chris out to dry. (Sorry is that a bit clearer )

Pardon?

I agree totally, that's when most people woke up to Mark

Yep it's ridiculous how it's been brushed over with how obvious it was. Especially since the crowd were chanting 'Liar! Liar! Liar!' during his eviction interview.

And now he's been hung out to dry.