Factual error: At the end, Sam reads a poem from a Mark Twain book and says, "Twain wrote it when his daughter died." But the poem, famous because it was engraved on the daughter's headstone, isn't by Twain, but by poet Robert Richardson. Twain never claimed authorship, so Sam couldn't be reading it with Twain's byline from any of his books.
Continuity mistake: As Sam is preparing to go on stage as Don Quixote, after catching the lead actor, a quick cut to Dulcinea dancing is shown. It is supposed to be Sam's love interest and ex piano teacher Nicole as Dulcinea. However, you can see Nicole standing in the background, in the pink outfit she was wearing in scenes from the beginning of the episode.
Continuity mistake: When Al is standing next to the juke box, Sam walks over to make a selection, and when Al starts talking his reflection is visible on the glass. Later in this episode, Sam is talking to Al at the sink of the dressing room at the ball park. As Sam looks into the mirror he says he thinks Al is a vampire, to which Al replies, "Neurological holograms don't reflect, Sam."
Continuity mistake: Though he's leaped into someone else, we always see Sam as Sam, dressed in all the host's clothes (including glasses or sunglasses). His host is revealed only in reflections. But here, when he looks at his host-self in the mirror, the hat and clothes are all identical - except that the reflection is wearing glasses, and Sam isn't.
Continuity mistake: After throwing the laundry bags out the back of the truck, close up shots on Sam and the girl show the back of the truck being relatively empty. However, the next shot from the rear of the truck has the back full of laundry bags again.
Factual error: The episode takes place November 9, 1965. After the haircut incident they are seen moving away from a theater with Doctor Zhivago on the marquee, but the movie was released December 22, 1965, a month and a half after the scene is supposed to take place.
Character mistake: In the preview for this episode, Charlie has trouble getting his countdown straight. He shouts that Sam is on in 50 seconds, then 47, then 48. In the episode itself, the mistake is corrected with a rather obvious overdub, changing the final number to 43.
Factual error: In the scene where the guy is telling Machiko about the major league teams that wanted him, he mentions the Indians, Yankees, and Orioles. The episode is set in 1953 and the story is from before World War II. While there had been a minor league team called the Orioles up to that point, there was no major league team called the Orioles until 1954.
Factual error: Though this episode takes place on April 1st, 1969, a freshly-painted sign in the park contradicts the date. In the scene with the hippies in which Sam is disguised as a meditating guru, the huge sign just behind him touts the San Diego Centennial Celebration - in 1968.
Revealing mistake: The background while Scott is on the raft with Brooke Shields is blatantly a studio wall. The clouds have streaks on them with dark colors and the seam where the ocean meets the wall can be spotted. The film "The Truman Show" used the same technique.
Revealing mistake: When Al jumps into the shot out of nowhere on the steps after the record producer leaves, Sam and the two girls abruptly move, giving away the technique to achieve Al showing up. The transition is usually smoother, this one happens to be rough and noticeable.
Other mistake: In the locker room, the old man's hair is pulled down over his right eye, away from the mirror as his right side is toward the wall. In the reflection, his hair is facing toward the mirror over his left eye, rather than away over his right.
Revealing mistake: Connie and Sam are talking in their room, while Sam is looking at his female self in the mirror. As Connie walks back into the shot, her shadow is cast on the wall behind the mirror. This indicates she came from the opposite direction that is possible in the reflection had this not been the mirror trick. In reality, she would have been coming from behind Sam, not from in front and wouldn't have cast a shadow on the wall with the mirror.
Factual error: When Sam knocks on Diana's door, she opens it. But we've just been told that she's completely deaf, so there's no way she could have heard him knocking. Though she dances to "vibrations in the air," this is with music played at volumes high enough to cause such vibrations. Sam is absolutely not banging on her door that loudly.
Continuity mistake: Near the end of the episode Michael Madsen's character attempts to run over Sam with a forklift, causing the boy to fall into the water and almost drown. As the boy is falling into the water, there is a wide shot of the action. In the scene, a box is being pushed over the edge into the harbor. In the close shot following, the box is gone, as are other items nearby.
Revealing mistake: When Sam is first looking at his reflection of himself in the glass at the beginning of the episode, the items behind his reflection do not match his point of view. A man walks through the shot and never leaves the frame, however is gone when the shot flips back to Sam.