Captain Wallace Casewell Jr., chief of police of Panama City, Florida, is the star of Killers of the Sea. Appointing himself protector of all Gulf of Mexico gamefish, Capt. Casewell makes it his mission to round up illegal fishing boats and to stave off such natural predators as sharks, whales and octopi. This may well be the only American film in which a school of dolphins are depicted as "the enemy." Beyond its rather ludicrous continuity, the film offers several spectacular underwater scenes, as Casewell battles invading sea life with knife and harpoon. This 49-minute documentary was narrated by Lowell Thomas.
| Actor | Role |
|---|---|
 Lowell ThomasNarrator | Narrator |
| WWallace Caswell Jr. Himself (as Captain Wallace Caswell Jr.) | Himself (as Captain Wallace Caswell Jr.) |
| ''Evolution' HendersonHimself | Himself |
| ''Spot' HayesHimself | Himself |
| HHubert DykesHimself | Himself |
| BBruce StillwellHimself | Himself |
| SSteve Beadon Himself | Himself |
| BBryant Lee Himself | Himself |
| JJulius Randy Himself | Himself |