Future Imperfect

During an away mission on Alpha Onias III, Riker is overcome by gas. He wakes in sickbay to learn that sixteen years have passed. He is now captain, Picard is an admiral, a disease has erased his memory of the intervening time, and he has a teenage son, Jean-Luc, whose mother has died. The Romulan Tomalak arrives for vital peace talks. Riker struggles to adapt, but things do not add up: the computer is slow, and his late wife turns out to be Minuet, a holodeck character. Accusing the Romulans of staging the whole thing to steal Federation secrets, he finds himself in a Romulan prison with a boy called Ethan. That too proves to be an illusion. Ethan is really an alien child, Barash, hidden alone by his dying mother with machines that create illusions. Riker offers him a home aboard the Enterprise.