Thom thought he had the podcast to himself, but it turns out the professor is back after 88 days at sea. 

It’s time for our submarine, or human occupied vehicle (HOV) if you’re posh, special. First we reunite ‘Vegemite and Haggis’ and talk to submarine pilot Tim Macdonald about his and Alan’s undersea adventures around Australia. Manganese nodule fields, gothic cathedrals, and an undersea UFO.

Life starts to imitate art. We chat with sci-fi author John Quentin who Alan has been consulting with while he writes his next book: The Galathea Legacy, about deep-ocean plastic pollution taking place at the site of the Galathea Expedition trawls in the Philippine Trench. A site which Alan and Tim recently dived… forcing John to tweak the draft as he strives for realism.

We then speak with Patrick Lahey and Frank Lombardo of Triton Submarines, a bespoke submarine manufacturer, about privately owned submersibles. Initially as luxury pleasure craft but we soon find out that there is a wide range of reasons why someone would want their own sub. Throughout their careers they have had many incredible experiences, like seeing a sixgill shark give birth and communicating with bioluminescent organisms.

The podcast wouldn’t be complete without checking in with Don Walsh. He tells us about the large commercial tourist submarines which have now produced more tourist submariners than the US navy.

It’s a packed episode but we sneak some news in there too. Deep-sea fishes have more variation in body shape than shallow-water fishes. A new species, genus, and family of brittle star from a lineage dating back to the Jurassic. Coelacanth can live up to a century and Mesobot, a new method for studying open water animals.