An old lighthouse keeper who lives with his daughter secretly keeps a prehistoric fish-man by feeding it scraps and fish. One day he misses the feeding and all hell breaks loose.

Cimarron City is an American Western television series, starring George Montgomery as Matt Rockford and John Smith as Lane Temple, that aired on NBC from October 11, 1958 until April 4, 1959. The name "Cimarron City" refers to a boom town in Logan County north of Oklahoma City. Rich in oil and gold, Cimarron City aspires to become the capital of the future state of Oklahoma, created in 1907.