This was Jeffrey Tambor's second TV role. On the set, he originally refused to play the role, because he was not happy with the way he was asked to play the character. He finally walked off the set, before all his scenes were filmed, because the filming was going late and he had to do the Sly Fox play at the Shubert Theater.
The killing by way of toys had been done 4 years prior, in The Illusion of the Lethal Playthings (1974) and--- just a few months earlier---in Mother Goose Is Running for His Life (1978).
Allan Miller appears as another character in season two's Starsky and Hutch: The Psychic (1977) and season three's Starsky and Hutch: A Body Worth Guarding (1978).
The music the hit man listens to is possibly from The Nutcracker ballet.