Knight Rider [Pilot; a.k.a. Knight of the Phoenix] (1) - S1-E1
Revealing mistake: When KITT takes part in the race and goes up on two wheels, you can see that the stunt driver is behind the wheel and that a dummy is strapped into the passenger's seat.
Revealing mistake: When Frasier comes into the chalet after skiing he doesn't show any of the visible effects after a hard day on the slopes. Meaning, his face isn't even flushed from the cold, his hair is perfectly combed after wearing a hat and there is not even a drop of snow on his boots.
Visible crew/equipment: During the Battle of Bull Run, just before the first shell is fired towards the plantation house, at the upper part of the screen you can see a helicopter flying over the battle action. (01:45:00)
Plot hole: Laura successfully knocks out both bad guys, steals their van and crashes through the warehouse doors. The van doesn't stall, but inexplicably, she stops it, gets out and runs away on foot, even though the baddies are coming to and coming after her. Not the option you'd expect a kidnap victim to choose: most people would floor it and keep on driving. (00:23:40)
Character mistake: When Alex mentions to Mallory that he's had sex before, he tells her he was 17 and that it was leap year. Not correct, this event occurred in 1982 (during one of the first episodes when Alex was 17), which was not a leap year.
Continuity mistake: Whenever Banner changes into Hulk his clothes rips, only his pants stays on. But when Hulk changes back to Banner, he suddenly has all his clothes on, no rips or tears at all.
Continuity mistake: When the man and his wife are checking out, we see the printer spitting out his bill which reads $1665.90 - yet when the man reads the amount, he says it's $1380.90. Director Mark Tinker comments on the discrepancy in the commentary.
Other mistake: T.J. Hooker and Vince Romano pursue two men who robbed the box office during a Beach Boys concert. The action takes place in the lobby of the Los Angeles Sports Arena, which is an indoor venue, but the footage of the Beach Boys performing is from an outdoor concert.
Up the Crick Without a Piddle - S7-E4
Visible crew/equipment: While Madam Fanny is rehearsing at the piano, behind her in the background, a woman comes down the stairs. It is not a waitress, and Rene and Edith are still in London.
Heaven Knows Mr. Utley - S1-E19
Continuity mistake: At breakfast Dick is telling Kirk about the U.F.O that George saw. He puts a bottle of syrup down. The shot changes and he is suddenly holding a fork.
Testimony of Evil (Dead Men Don't Laugh) - S1-E6
Continuity mistake: At the start, the glass on the left is poisoned. The guy picks up the glass on the right, but still ends up dying.
Me and Mr. T - S1-E4
Continuity mistake: When the teacher is asking the class questions about the declaration of independence, she has some info about it written on the blackboard ending with "1776 in." Then facing away from the blackboard, she asks a question and Mr. T quickly answers and then only a second later, the camera is back on the teacher and suddenly the world "PHILADELPHIA" is on the blackboard under the "1776 in" with no time for her to have written that word in one second.
Lisa's Song - S3-E14
Factual error: Doris finds out that Gypsy Queen "Lisa" died from influenza around 1918, so she didn't get to star in her performance. However, when Doris and Lisa's ghost are singing their duet later, Lisa's hair and costume are 1980s style, instead of the era she died.
Factual error: The forces of Cassiopeia all sport the crown-like "W" sign which is the shape of that constellation... but only as seen from earth! These five points in three-dimensional space (like all star signs named after anything) look like that when viewed from our own planet; but from anywhere else, they aren't shaped like that at all. Why would they chose to see themselves through a very specific angle of view from some other distant planet (earth)?