A uniformly superior guest cast greatly aids this installment. Solo and Kuryakin are trying to prevent THRUSH from glomming onto a boy genius whose father early in the action meets a bizarre and series-typical, roundabout end. The boy is played by Jay North, who a few years earlier was TV's "Dennis the Menace." North is just right for the part. Other luminaries contributing to the fun include Diane McBain, John Hoyt, Arnold Moss, and Angela Lansbury (who gobbles up everyone else in her scenes). Vaughn and Callum are at their whimsical best portraying UNCLE's best. In a departure from norm, their characters both get to make a run at this episode's femme fatale, played by the lovely McBain with a more than usual action bent. Hand-held exterior camera shots - - another trademark of the series -- contribute to what, in the mid-60s, was production quality superior to most TV network action series of the time. This episode makes several allusions to earlier installments, including having one of our heroes and the femme of the moment hanging in a dank room and toy planes as weapons (the series predicted weapons drones). A "goof" noted on this episode's IMDb main page is not actually erroneous. Solo is indeed Section 2, Number 1, i.e., UNCLE's top enforcement agent, as was established in Season 1 (Solo identifies himself as such). The numbers on UNCLE security badges are not meant to correspond to the agent's place in the organization's hierarchy.