goosebumps: ghost camp

Harry and his younger brother Alex goes to Camp sprit moon. Everyone are really nice to them and the camp is absouletly awesome. But Lucy who is one of the girls in camp sprit moon, tells that everyone in the camps are ghosts including herself. Thinking that it's crazy, Harry doesn't accept Lucy's sprit to control his mind. Thinking that he must escape he runs to Alex and runs. Alex tells him that the same thing happened to him. Suddenly all of the campers trap them...! But all the creeping sprits fight to go in to the body. Yes! All of a sudden they all disappear but Alex is weird. Alex is a great singer but as he hums...the voice is Elvis'! And Harry realises it gripped in horror...