Morag and Demelza, Sir Gadabout's old adversaries, have taken over the pet shop in Camelot village. They have adopted elaborate disguises, are keeping the real owner under lock and key, and intend to cause so much chaos at the Round Table that they will be able to move in and install themselves as king and queen. The knights at Camelot begin to realize that their pet food is having a strange effect and that pets they bought from the shop aren't all they expected; Sir Gadabout himself has a little lizard which grows rapidly into a crocodile and terrifies everyone! The cause of the problem is eventually traced back to the pet shop and our determined knight is sent to investigate.