Stingray

Following the destruction of a WASP submarine, Troy and Phones are sent to investigate. They are soon captured by an enemy submarine in the form of a gigantic fish, which takes them to the underwater city Titanica. There, they meet Titan for the first time.

The Stingray crew track the launch site of missiles fired on Marineville to a volcanic island. However, on investigating they become captured by the aliens responsible.

Commander Shore and Phones are taken prisoner by Idotee who uses an old Spanish galleon to attack ships. Shore demands that Troy launch Sting Missiles against the galleon but the Captain disobeys orders and boards the vessel. There he opens his air cyclinders in the control room but unknown to Idotee the cylinders are filled with laughing gas! The alien is laughing so hard he fails to realise that he's captured

When their vacation is cancelled, the Stingray crew probes into the ocean depths, They discover a deep shaft that leads to desert-like plateaus. Before they can complete their investigation, a wall of water turns the desert into an underground sea. Swimming desperately back to Stingray they attempt to relocate the shaft before their oxygen runs out. Out of desperation they enter the first shaft they see. They surface near a beautiful tropical island. The perfect place for a holiday

Commander Shore's friend Admiral Denver claims to have seen the Loch Ness Monster. As a result, the Stingray crew travel to Scotland to see if the legendary beast exists.

Shore takes up Admiral Denver's challenge that the WASP's of today can't take the rigours of an old-time sailing vessel. Phones and Lt. Fisher are assigned to Denver's crew. When a storm hits, Denver is knocked out and loses his memory and Phones and Fisher are cast adrift in a small dinghy. They are rescued by Troy who has been following in Stingray but, when Stingray approaches the sail boat, Denver begins firing his guns wildly at the sub. Troy, however, succeeds in overpowering Denver who later regains his memory in hospital.

Troy locks horns with the boastful Naval Captain who arrives in Marineville to demonstrate a new missile. X20, however, loads the test missile with real explosives and it appears that the Naval Captain is actually out to kill Troy. Shore is ready to Court Martial the Captain until Troy proves the interference of Titan's subjects.

Phones is convinced that he is unfit for duty when X20's plan to discredit him nearly succeeds. Disguised as a psychiatrist. X20 further discredits Phones' claim that he really did hear the sounding that drew Stingray away from their escort patrol. It's Lt. Fisher who discovers X20's remote sounding device that clears Phones.

While the Stingray crew go to the rescue of two crazy treasure hunters, Troy falls down a crevasse, runs out of air and goes into unconsciousness. When he comes to, he discovers he doesn't need breathing equipment to breathe and he is now the richest man in the world.

Thinking all the commotion at Marineville signals the visit of a VIP, X20 kidnaps the man and delivers him to Titan. The undersea ruler is surprised to learn that X20 has brought Duke Dexter, a pop singer. Titan is convinced that Dexter is an ally of the underwater people by the way he drives the Terraneans crazy with the weird noises he emits. Dexter is freed by Titan to continue his 'good work'.