Synopsis by Hans J. Wollstein
Chapter eight of Republic's S.O.S. Coast Guard reveals that intrepid coast guard officer Terry Kent (Ralph Byrd) survived his underwater troubles. Certain evidence leads Terry, his reporter girlfriend Jean (Maxine Doyle), and photographer Snapper McGee (Lee Ford) to a kelp plant that is actually the secret hideout of Boroff (Bela Lugosi). Quickly covering all evidence of wrongdoing, Boroff and his minions hospitably show the guests around the plant but Snapper accidentally photographs some canisters containing the secret ingredient used to manufacture disintegration gas. Learning that the radioactive components may show up on Snapper's snapshot, Boroff assigns his men to follow the photographer and destroy the film. A harrowing chase ends with the gang forcing Terry's car off the road and over a cliff.