I was wondering how Nick got up there as well. That was on my mind last night.
I agree with PK, the last few minutes were ridiculously OTT.
Certainly with Ben in tow, and I don't really see how he could get him up there. Make Ben go first and ther'd be some kind of evidence of a struggle, but second and he wouldn't have gone, 'cause it's not as if Martin carries a gun round or anything.