Killer in the school

You duck just in time. The knife swings away and misses you. You then grab your attacker and throw him to the floor. You begin to strangle him before you realise who it is... "Andrew!" You immedietly pick Andrew up from the floor. "Why did you try to kill me?" you demand. "I thought you were him" Andrew stammered. "Who?" you ask. "The hooded man" replied Andrew "he's the one whos been doing all this. I've been hiding in here with Cameron since it happened"
Suddenly Cameron steps out of the shadows. "We survived this long, we should head for the library thats where everyone is heading" You agree. You must go to the library.