It is such a shame when actors and actresses of high quality get involved with pure crap, probably because they were offered a great deal of money. Not one of Helen Mirren's better career moves. The acting of the "teens" is simply appalling, not helped by a script that is in parts simply inept.
Most of Kevin Williamson's work is above average box office dross, but this is really below par.
This is the sort of movie that you watch on TV when there is nothing better on and you have had half a bottle of wine to drink and are waiting for the Pizza to be delivered so you can drink the other half.