This is one of those “what’s real??” Stories, which I don’t generally care about, because it’s sort of an A or B type scenario – not a huge mystery. Either its real or it isn’t. And of course since it’s an episode of TNG, we know Riker isn’t crazy, so there’s even less suspense. If the episode had *anything* going on beyond that “is Riker crazy” question, it might’ve been okay, but there isn’t anything. The reasons for why he is being manipulated aren’t interesting or addressed in anything other than a cursory way. Riker doesn’t really have to fight his way out, or learn anything. He just sort of runs down the clock yelling a lot, and then is rescued.