I wanted to vote Nice Warrior but I realized that was because Mars being the source planet made me happy and if that was all that tipped it out of lukewarm that was not enough.
I couldn't get over the Professor having his nice little cheering-Clara chat while sitting in an OPEN DOORWAY with his back to a room/corridor from which the enemy could easily come. No one sits with their back to an open doorway while fleeing for their life from an mysterious alien.
Also the 80's name dropping seemed unusually lame.
It was a gazillion times better than last week though.