In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Q: Sentence1: Joe and Fred like to scuba dive in Puget Sound. Sentence2: One time they found a big wolf eel underwater. Sentence3: The fish sunk his teeth deeply into Joe's scalp. Sentence4: Fred cut of the head of the fish while it was still attached to Joe. Sentence5: Only a doctor at the hospital could safely remove the fish head.
A:
Wolf eel, A doctor, Joe, Fred