Underwater and Undercover
Neri returns to help Dianne with her oceanographic survey leaving Mera alone on the island to face a UBRI search party that has come to the island looking for them. Mick catches a glimpse of Neri and Mera on a monitor but everyone tries to make him think that he is just seeing things. He persists in his claim of having seen two girls but only Liselle, who is working as an UBRI spy, takes any interest. His story eventually gets back to UBRI where Dr. Hellegren plans to step up his search for the girls. When Dianne learns that Sam has been keeping his discovery of the titanium deposit a secret with hopes of cashing in on the discovery, Dianne asks him not to pursue it.