Treasure Down Below is the fifth produced episode and the twenty-fourth broadcast episode of the series Stingray.
While on shore leave, the Stingray crew find buried Treasure, underwater pirates and a Captain that would do anything for Gold.
On board a cruise ship, Captain Black sails it away, having just recently left his crew on an island and taken all of the gold they found, for himself. While stirring the ship he drinks some rum, and he does not know that he is heading for an iceberg. Before he can do anything, he hits the iceberg and the ship sinks.
Three months later, Troy, Phones and Marina are on shore leave in Casablanca. While Troy and Marina are out at a restaurant, Phones is left to guard the ship. While on board a person sells Phones a map leading to treasure.
When he explains this to Troy he says that he’s been conned. Phones continues to explain that they’re right near the treasure. Phones feels bad about it as he had to borrow money off Troy to buy it. He forgets about it and retires for the night. Marina, wanting to help Phones, secretly sets a course for the treasure.
When Troy and Phones wake up, they are amazed to find they are off course by miles. So Troy decides they may as well look for the Treasure since they are so close to the area. Suddenly they are caught in some massive whirl pool and Stingray is pulled all the way down to the sea bed.
Back at Marineville a huge search has begun as Stingray has not reported in.
Troy surfaces Stingray, where the crew find themselves in a cave. Troy, Phones and Marina step outside where they find the treasure, but two marine people called Ebrun and Trell appear and lock them in a cell. Troy and Phones discover Captain Black is being held prisoner as well.
They all manage to escape, but Black insists they should take the treasure as well. Troy disagrees and so Black joins up with Ebrun and Trell, who capture Phones and Marina, but Troy manages to escape.
They tie Phones and Marina to racks were Black twists the tightner. Then Troy appears and saves Phones and Marina, overpowering Ebrun, Black and Trell.
- In the digitally re-mastered version extra music is added when Search Vessel 2 reports not finding Stingray.
- Troy and Marina's visit to Casablanca is shown in the closing titles of every episode.
- Ebrun appears to be wearing a candelabra on his head.
- Black reveals that he has been in Ebrun and Trell's hideout for three months.
- When Atlanta tells Search Vessel 2 to keep in touch, Don Mason replies instead of David Graham.