 A prowler is on the loose in Bedrock. To prepare for safety against this perpetrator, Betty takes judo classes from Mr Hashimoto. Wilma wants to join, but Fred keeps her to do so since those courses cost too much. However, she takes them anyway and Fred wants to give her a lesson by dressing as a prowler overnight. But the real prowler happens to come the same night. This promises to be quite a night for the Flintstones and the Rubbles, "that s for sure" !