Ep 14. Whom Gods Destroy

Captain Kirk and his crew of the USS Enterprise are sent to a large established asylum, Elba II, to transport a new medicine that could cure mental illness. They arrive to find that the asylum has been taken over by two patients who have gained control over the facility and the staff. Garth of Izar, once a Starfleet captain and the other, Dr. Severin, a specialist in therapeutic techniques.

The Enterprise crew members beam down to the surface to deliver the medicine to the asylum, but they are met with hostility from the patients. Captain Kirk and Mr. Spock soon learn that Garth, who has the power to shapeshift, has taken over the asylum and is using his ability to manipulate the minds of the staff. He has also taken Dr. Severin under his control and plans to use him to take over the galaxy.

In an attempt to convince Garth to surrender, Kirk and Spock offer to take Garth aboard the Enterprise to be treated for his condition. However, Garth sees through their plan and creates a diversion, allowing him to escape.

The crew members of the Enterprise are then subjected to a series of tests and manipulations by Garth, who has taken on the appearance of several crew members in order to undermine their trust in one another. Meanwhile, Dr. Severin is attempting to create a bomb that he believes will set him and Garth free once and for all.

As the situation becomes more dire, Captain Kirk and his crew must figure out a way to stop Garth and Dr. Severin before they succeed in their plan to take over the galaxy. This episode explores the themes of power and control, as Kirk and his crew struggle to maintain order in the face of chaos and manipulation. It also features notable guest stars, including Steve Ihnat as Garth and Yvonne Craig as Marta, a former follower of Garth who Kirk and Spock hope will be able to help them stop him.