- For other uses, see Jennings.
Jennings and Williams were security personnel who accompanied Spock, Leonard McCoy and Doctor Stephen Mohr on a tour of the ruins of the last remaining city on Heitius VII. Nearby, a group of scientists discovered three ancient cyborg mummies stored in an old laboratory. Williams accidentally leaned against a control and reanimated the mummies. Jennings and Williams fired phasers at the mummies, but they were defended by a force field. Jennings was punched hard in the chin and knocked out.
When the rest of the landing party came to, the mummies were attempting to convert Jennings into a cyborg. Luckily, however, the cyborgs' internal power supply ran dry before they could harm him. (TOS comic: "The Mummies of Heitius VII")
- Jennings appeared on the cover in an operations division red shirt, but wore a green shirt in the story, along with the other security guards.