Faced with a critical power-shortage after Smith messes up, the Robinsons are forced to sacrifice the robot for the greater good, prompting the morose mechanoid to depart for the "Valley of Shadows" where, rather than simply powering-down with dignity, it finds itself blown up to gargantuan proportions by the valley's mysterious radioactive gasses. This minimalist episode has no guest-star or guest-monster, offers up a simple story (likely inspired by the success of 'Fantastic Voyage' (released a few months earlier) as Will and Smith enter the iron giant to try to fix the problem), and frugal production values (the 'inner robot' sets are mostly recycled props from earlier episodes), but is moderately interesting (especially the encounters with the robot's 'immune system'). Like most LiS episodes, there are internal inconsistencies, notably in the robot's response to being shut-down/turned-off (which has happened numerous times in past episodes), the weak 'special effects' in the climatic scenes when the robot begins to shrink (only the spaces between its inner bits get smaller), and the final scene by the chariot, which suggests that everything that happened previously was completely unnecessary. The "bubble-headed booby" is now clearly a sentient, self-aware and feeling entity, and the three-way relationship between the robot, Smith, and Will dominates many story-lines (for good or for bad). The lack of yet another strange, eccentric or comic person inexplicably appearing on the planet is a refreshing change.
