After Borg and family matters, TNG turns back to conceptual techie sci-fi when Wesley's experiments with a "warp bubble" have bizarre consequences for the ship and/or Wesley's mother. (Hint: "And/or" is a clue that this story is not what it seems.) There's a flash of light, and suddenly people start to go missing from Beverly Crusher's world. It starts with her visiting old friend, Dr. Quaice (Bill Erwin). He vanishes without a trace, along with all records pertaining to his visit and, for that matter, his entire life and career. There's nothing to suggest he ever existed, except Crusher's say-so. Before long, more go missing, including Crusher's medical staff and most the crew. No one but Crusher notices any difference; to them it has always been this way.
"Remember Me" is a clever and inventive depiction of how well-argued logic and personal conviction prove useless when the physical evidence doesn't support them. Crusher can talk and talk and make perfect sense from her point of view, but she comes across to everybody else as delusional because they can't see the proof of her assertions. As a mystery, the story is deftly structured: It gives you hints about the true nature of What's Wrong Here (is it Crusher, the universe, or the fact that Crusher is in another universe?) but it never completely tips its hand until we have completely identified with Crusher's state of mind — which is one of increasing panic as the entire universe seems to be slipping away. Meanwhile, energy vortexes appear out of nowhere and threaten to suck her in.
To me, the absurd highlight of the episode is the scene on the bridge where Crusher and Picard are the only people left — in the universe, it would seem. Crusher tries with pure logic to destroy the notion that the universe consists of two people cruising around in a starship. And yet Picard assures her that's exactly what the universe is. He completely believes it. If such a cosmic joke were happening to you, you would go mad.
The twist (nicely executed but not played for suspense or surprise, as that would be self-defeating) is that Crusher is trapped in a micro-universe created by her own mind as a side effect of Wesley's "warp bubble" experiment. The vortexes are actually the crew's attempts to retrieve her. When that fails, the story turns to more metaphysical matters involving the reappearance, in a nice bit of continuity, of the Traveler (see "Where No One Has Gone Before"), who helps Wesley bring his mother back to the real universe through methods that transcend space and time. "Remember Me" has no shortage of exposition or technobabble, but as these things go, it's one of the most purely intriguing.