Mac goes undercover to help Harm investigate charges of sexual misconduct against Chief Petty Officer Merker who is the leader of the Wiccans, a local witches coven with many Navy members. The female seaman who brought the charges claims she was seduced when she fell under the man's spell, but Merker claims the sex was consensual. The Wiccan's attorney is sharp and claims his client is the unfortunate victim. However, Mac learns that another young woman suffered the same fate. He convinces her to testify and Merker is found guilty.

Later, Mac learns that Mic Brumby was also thrown into a compromising position while undercover in the Royal Australian Navy.