Killer in the school

"You killed my friends!" you cry "so i'll kill you!". You pull Andrews dagger from his belt and lift it ready to strike. You are about to push it down when a hand grabs your arm and pushes you away. The knife is knocked to one side. The person who stopped you now stands over you. "Sam!" you choke out "please dont say you're with Andrew!" "Sorry" he replys "but Andrews offer was too great" Sam and Andrew begin to laugh. "Me and Sam were working together the whole time" Andrew continued "I knew you would trust Sam so I made him trick you. Who made you search the school so that I could attack you? Who made you come to the library? Who showed you the secret passage in the library? Who led you into a classroom so that you couldent escape? Sam did". "But Andrew you were with me when you were attacked, I heard your screams" you mumble. "Ah yes" Andrew replys "that was a clever trick. Sam merely pulled me in and used a sound effects tape to make you think I was being attacked. It stopped you from ever thinking me and Sam were doing the killing. Anyway this is enough talk, it is time for you to die!" He walks towards you. Will you: