This Riker episode (not to be confused with the second TNG motion picture) is a rare Star Trek episode written from the aliens' point of view, although the aliens themselves are an allegorical reference to mankind. (In fact, the story is simply a remake of the 1951 film "The Day the Earth Stood Still".) The structure of the episode is the classic A/B form, with the A story featuring Riker on the planet and the B story featuring Picard's efforts to recover him. Jonathan Frakes (Riker) is excellent, delivering the right amount of comedy and drama with each of his scenes. Picard, as usual, stands out as well with another great performance by Patrick Stewart. A particularly character-rich episode, the story is also enriched by some wonderful performances from several different guest stars as well. A great one!