Star Trek (1966) - 41 major mistakes

Deliberate "mistake": Special effects of the ship in space were very expensive in the 60s and couldn't be wasted. So when a larger model was built with slightly different nacelles, shots of both versions became common, even within the same episode. This is why the Enterprise sometimes had red needle-tipped nacelles and sometimes lighted "spinning" ones, and in aft views she had either round white balls or perforated vents at the nacelles' ends.

Visible crew/equipment: "The Cage": When the doctor is mixing the drink and Pike gets up off the bed to accept it, an equipment shadow sweeps across the left side of the screen.

Plot hole: "The Cage": Pike says he doesn't want women on his bridge, Number One being the one and only exception, and he keeps ordering Colt off it. His apology to Number One indicates that A)he doesn't think of her as female, and B)she's the only exception to his rule. So how does he overlook the very female crew-woman seated at the science station?

Continuity: When Rand brings Sulu the plate of food, it has a bowl of colored cubes on it. Then there's a cut to a close-up of Sulu eating the cubes and the bowl is now a plate. Then in the long shot it's a bowl again.

Continuity: As Kirk and Spock prepare to enter the time portal, Spock deliberately places the tricorder at his left side, holding it there with his left hand. As they appear in 1930 earth, he is holding the tricorder with his right hand and his left hand is free.

Visible crew/equipment: You can see the shadow of a boom mike on a tree just after the Caretaker appears.

Continuity: Kirk and McCoy are in the Exeter's engineering section when Kirk uses the intercom to ask if anyone is aboard. Several shots of the deserted ship follow as his voice echoes off the walls, including one of engineering - with Kirk and McCoy suddenly, mysteriously absent.

Revealing: "The Cage": When the laser cannon starts firing at the Talosian rockface, a styrofoam block falls and rolls away on the left side of the screen. After a brief shot of the crew, we see the cannon still firing, and the exact same block falls and rolls off screen on the left again.

Continuity: Kyle reports the landing party's whereabouts on the surface, and Spock asks, "And Apollo?" Kirk had no chance to call the ship after Apollo revealed his name - so Spock should not have known it.

Other: Spock and McCoy have a brief argument over whether Charlie could have survived on his own all those years. Because they're talking at the same time, Spock saying "Doctor" as McCoy says "Mr. Spock," the closed captioner apparently misunderstood McCoy's line. The caption has him calling Spock "Dr. Spock."

Visible crew/equipment: In the scene where Dr. Dehnar is talking to Gary Mitchell in sick bay, when he grabs her arm you can see the shadow of the boom mike on the door and adjacent wall.

Deliberate "mistake": So that he can look in the right direction, toward Lincoln, a shot of Kirk is reversed before the first battle, putting his uniform insignia on the wrong side.

Visible crew/equipment: A camera shadow briefly intrudes on the right side of the screen as Kirk asks Mr. Scott about the sensor readings.

Visible crew/equipment: When Kirk turns to follow Miranda across the arboretum, the camera shadow is briefly visible on the wall at the lower left of the screen.

Continuity: When Capt. Kirk and Charlie enter the turbolift heading for the bridge, Kirk is wearing one style of tunic and when the turbolift arrives on the bridge, Kirk is wearing a completely different tunic.

Revealing: When Kirk beams up from the planet, the insignia on his shirt is not there.

Continuity: The landing party is out of contact with the Enterprise for two days because of the missing communicators. Wouldn't the Enterprise notice at some point and beam down some more, or make some other attempt to contact Kirk & Co.?

Continuity: When the android Kirk boards the Enterprise and takes a "command pack," he walks out and down to the transporter, but he doesn't have the pack in his hand.

Revealing: Kirk orders Marple to cut around a rock to the right and make a noise to distract their observer. But the actor appears to slightly screw up his cue: Marple promptly traverses the rock to the left instead of the right.

Continuity: After Edith stumbles and nearly falls down the stairs, she still has both her shoes on. But after the kiss, she proceeds up the stairs and is now carrying one shoe. She had no time to take it off, as she was, er, busy with Kirk the whole time.