A welcome new take on the slasher genre, Kill Theory starts out quite well, but soon deteriorates into TV teen-soap territory because of the ill thought out character relationships.
The titular kill theory of the villain only works because the characters are pretty shallow and have a common backstory straight out of a bad Gossip Girl story strand. It would have been much more interesting if the group dynamic at least resembled one from the real world where friends do not necessarily hold old grudges and girls might not viciously fight over guys who seemingly do not even deserve it. This way the plot becomes repetitive and predictable quite soon.
It's sad that instead of really working the new angle, the filmmakers only used it as a hook to dress up the same old same old. Acting is solid throughout, apart from one spectacularly bad choice. The actor playing the "put upon fat guy with strong complexes and deep resentment waiting to surface" plays just that with all the cliché choices one might associate with the cliché role, plus overacts so badly that he completely kills all the scenes he is in. He should go back to acting school or look up "restraint" in the dictionary. (To be fair to him, the director might also be to blame; how could he let the guy screw up so disastrously is beyond belief - are they close friends or relatives?) All in all, a film that one might pass the time with but nothing memorable.
