Doing a selective re-read on some of the earliest ST titles and am currently on this one. Without getting into too much detail, portions of it involve a pre-WNMHGB Gary Mitchell and Elizabeth Dehner. They have time-traveled to the twenty-first century and are using cover names. Dr. Dehner's cover name is Dr. Bellero. Never picked up on it before but Bellero was the name of a character on an episode of "The Outer Limits" played by, you guessed it, Sally Kellerman. Pretty funny.