Captain Payne (Peter Williams), Janet Slayton (Ingrid Sylvester) and Peter Blake (Stewart Cuidotti) are in Dr. Carey’s (Delena Kidd) lab. Peter tells them that he believes Mark Bannerman (Gerald Flood) went out on the guyot looking for the Phenicium. When a diver returns it turns out to be Dr. Deraad (Richard Coleman). He tells them that Bannerman was attacked. Peter and Deraad rush out and rescue him. Peter accuses Deraad of attacking Bannerman, but Mark confirms that someone else was out there.
By now everyone is looking suspicious. Just about anyone could be the second saboteur. Dr. Deraad tells everyone that the only metal he is interested in is gold. The person that attacked Bannerman hid their mask and aqualung in Professor Gordon’s (Robert James) lab. Professor Soobiah (David Spenser) was found wandering around and Dr. Carey knows her way around the guyot and can maneuver the deadly current that surrounds Aegiria. Bannerman begins to look a little closer at Dr. Carey when there is an explosion in her lab, with her in it.
Captain Payne decides that he needs to close down Aegiria until the saboteurs are found and there is proof to back up any suspicions. Bannerman disagrees with that decision. He feels that they would be playing into the saboteurs’ hands if they stop the drilling. Payne is concerned for the welfare of everyone in Aegiria and is adamant.
The UN decides to turn the drilling over to a company who will take on the research program. The company turns out to be International Metals Limited. The same company that hired Dr. Deraad and the mystery person who is sabotaging the UN’s work in Aegiria.
Dr. Deraad receives a note to meet him that night in his lab. When he gets there, he finds out who the other saboteur is.