Synopsis by Hans J. Wollstein
The car chauffeured by Pidge (David Oliver) comes to a halt just before crashing off the bridge. Agent Tommy Dawson (Henry Hunter), meanwhile, did not only survive being thrown from Brenda's car, but had the prescience to grab the Belgravian crown jewels on his way out. Important clues lead Agent X-9 (Scott Kolk) and Pidge to the waterfront store where Blackstone (Henry Brandon) is keeping Baron Karsten (Monte Blue) imprisoned. In the inevitable storefront fight between X-9 and Sebastian (Jack Cheatham), one of Victor Brenda's henchmen, a harpoon is accidentally fired.