One of my favorite episodes,in tone it stands alone from the rest as it is creepy,weird and unsettling. Members of the crew are having difficulty in sleeping,and after a terrific scene in the holodeck,manage to recreate an alien abduction table,and then find that Riker has had his arm surgically amputated and then reattached! *shudder* very effective,great writing and conclusion. It's pretty wonderful and is one of the many I love to watch over and over.