Thirteen days have passed since the return of the MARCO POLO from the parallel universe. The crew enjoys its leisure time and a well-deserved vacation. However the Chief Psychologist, Dr. Thunar Eysbert, determines that the crew, to include himself, are undergoing a change. Every form of sense of duty seems to have disappeared in the men who now only consider their hobbies as important. And although this illness attacks also him, Eysbert decides to tell Perry Rhodan about it.

However also Perry Rhodan is on vacation, and so Eysbert establishes contact with Pucky and Icho Tolot, that also became distrustful of him since he is susceptible to and displays the symptoms of the illness that he himself has named the PAD-Epidemic (Plague). Pucky, Icho Talot and Eysbert tell Reginald Bell and Galbraith Deighton about their suspicions and decide to contact Rhodan. However Rhodan disregards their warnings and doesn't dream of interrupting his vacation on Fiji and leaving his vacation-flirt. Pucky comes back again disappointed and now tries to find Atlan.

In the meantime, some crew members of the MARCO POLO behave strangely. Mart Hung-Chuin, the chief physicist of the ship, plunges into his work and disregards safety measures, so that he detonates a whole research-asteroid. With Major Byerlin, racism suddenly breaks out, and he attacks a Springer-base. Finally, Fellmer Lloyd, who is on vacation on Wolf 28, disregards the command to return to Terrania City as quickly as possible, because he would rather spend his time collecting minerals.

After all these incidents, Atlan and Bell are convinced of the existence and the dangerousness of the PAD-Epidemic. They begin by looking for all 8,000 crew members of the MARCO POLO and accommodating them in a quarantine-station on the moon in order to be able to observe them better. One of the first realizations is that the symptoms of the epidemic can be overcome through mere willpower. Eysbert himself is the best example of this.

The single one, that still appears unimpressed, is Perry Rhodan, who still enjoys his vacation on his island.