This was a very good psychological thriller, dealing with how psychotherapy can be misused in the wrong hands. I remember reading a Sherlock Holmes story in which he observed that "when a doctor goes wrong, he is the first of criminals", and as this episode unfolded I could see one such glaring example. When the deranged Simon van Gelder exploded onto the bridge of the Enterprise and it was found that he was, not an inmate, but an associate of Dr. Adams who had been victimized by the "neural neutralizer", an investigation was imperative. The key to the whole thing was one of the most dramatic scenes in the history of Trek---the first use of the Vulcan mind-meld on a human---and a lot of credit has to go to Dr. McCoy, who for all that he called himself an old-fashioned country doctor was light-years ahead of everyone else; he was the one who pushed the reluctant Vulcan with the urgent "Will it work---or not?" Spock actually performed what I immediately recognized as a quieter version of the Vulcan mind-fusion combined with telepathic hypnosis (and Leonard Nimoy really pulled a fast one on the network censors!); he delivered two quiet, half-whispered suggestions of well-being, relaxation and of weightless suspension, which exerted a calming effect on van Gelder's mind and enabled him to describe his ordeal. And eventually the now-deranged Dr. Adams fell victim to his own nefarious machinations, while van Gelder was restored to sanity by the same Vulcan mind-fusion and took over the direction of the penal colony. +As I watched Spock in action I started to get a new appreciation of what the Vulcans call "wuh tepul t'wuh kashek"---the power of the mind and what it could be capable of. And I recognized the truth of the Sherlock Holmes observation.
Review of Dagger of the Mind
