Again a bet was made with Sullivan - and he sent Transfer to cause havoc. This time, however, more people believed in Willy Fog, although all of them (apart from Lord Guinness) turned against him at times - when reports came back that the volcano they journeyed into was about to erupt. Romy, Tico and Rigadon went with Willy on the voyage again and were joined by Professor Lidenbrock - an expert in archeology and Hans - an Icelandic who acted as a general dogsbody. The team again made it - just in time to win the bet.

Willy was invited to help investigate strange goings on - several ships had been attacked by what seemed to be a sea monster. Willy, Romy, Rigadon and Tico went, although soon the ship they were on was invaded and they, alongside Ned the harpoonist (very like Hans from the previous story) and another Professor, were kidnapped by the mysterious Captain Nemo. After having adventures under the sea, they finally escaped