Surf's Up! Joker's Under! - S3-E10
Other mistake: An amazingly precognizant Dick Grayson is already wearing his surfing togs before Commissioner Gordon calls to say that Joker has invaded the surfing community. (00:04:30)
Suggested correction: Dick isn't amazingly precognizant. He's wearing swim trunks while using the rag to prep his own surfboard. Barbara Gordon was already at the beach with Skip, and Dick is heading to the beach with his surfboard as well (00:04:34).
A Horse of Another Color (2) - S3-E5
Revealing mistake: Ethel Merman just can't keep a straight face amidst Batman's campy silliness. Here and in the previous episode, she can be seen cracking up in several of her scenes with Burgess Meredith. (00:05:00)
Enter Batgirl, Exit Penguin - S3-E1
Plot hole: When he abducts Alfred, believing him to be a minister, Penguin suffers a peculiar memory lapse. He's encountered Alfred twice before in previous episodes, even kidnapped him once before (knowing full well that he was Bruce Wayne's butler). Yet here, he fails to recognize Alfred at all. (00:12:30)
Nora Clavicle and the Ladies' Crime Club - S3-E19
Revealing mistake: Not only does Batman's solo flute play two music tracks at once, it also keeps on playing after he's taken it out of his mouth. (00:20:00)
A Horse of Another Color (2) - S3-E5
Visible crew/equipment: The stunt rider doubling Penguin in the horse race is pretty easy to spot. He's younger and thinner (despite an obviously padded costume), and his nose is about two inches shorter. (00:18:00)
I'll Be a Mummy's Uncle - S3-E23
Plot hole: After the rock falls on King Tut at the end giving him amnesia, Batman explains how the rock fell. He says Tut raised his voice three decibels above high C. Decibels are a measure of volume, while pitch is a measure of frequency: the two are not directly related. This mistake was done in other episodes of Batman also, such as when Joan Collins played the villain.
How to Hatch a Dinosaur (2) - S3-E9
Factual error: Gotham City's museum should brush up on its paleontology. Their sign claims the neosaurus egg is 40 million years old. A) Neosaurus lived in the early Permian period, 290 million years ago. And B) All dinosaurs were rendered extinct 65 million years ago, most likely by an asteroid strike. So 40 million years ago, there were no dinosaurs on Earth. (00:06:50)
The Joker's Flying Saucer - S3-E24
Continuity mistake: Batman and Robin both leap into the Batmobile and roar out of the Batcave. But the stock shot used after that shows Batman alone in the car. (00:03:10)
The Joker's Flying Saucer - S3-E24
Continuity mistake: Aboard Joker's flying saucer, Alfred and Batgirl are sitting three feet apart, then shoulder-to-shoulder, then apart again, depending on the shot. (00:20:50)
The Foggiest Notion (2) - S3-E12
Factual error: The British curator from whom Lord Ffogg steals a collection of artifacts needs to go back to school (or someone in Batman's prop dept. does). While most of the signs are correctly spelled and punctuated ("Duchess of Desborough's Diamonds," "Her Majesty's Priceless Snuffboxes," etc.), the one marked "Lady Easterlands Jeweled Easter Eggs" is missing its requisite possessive apostrophe. (The closed captioner noticed, though, and corrected the mistake there). (00:11:15)
The Unkindest Tut of All - S3-E6
Continuity mistake: When the Batmobile pulls up to the theater where Tut's henchmen are emerging, Batman challenges them while standing at the open driver's side door. You can see his left hand closing the door, as well as hear it click shut - but in the next, reverse angle shot, as he and Robin leap into the fray, the car door is standing wide open again. (00:08:00)
The Joker's Flying Saucer - S3-E24
Character mistake: Vertigris tells Joker he planted a bomb in the Batmobile while it was parked in front of City Hall/Police HQ. Only in this instance, it wasn't. It was parked in the alley out back, the better to hide his bomb-planting from public view, so it's strange that he'd forget this. (00:08:15)
Continuity mistake: Lila comes through the bead curtain with the poison lilacs wrapped in green tissue paper. She drops the flowers, and in the next shot of them on the floor, the blooms don't even remotely resemble the ones she was just carrying - and the green paper has disappeared altogether. (00:10:55)
The Entrancing Dr. Cassandra - S3-E25
Continuity mistake: The Batmobile returns to the Batcave by remote control. It's facing left when we get a brief, three-second shot of Batgirl talking to Batman and Robin. In the very next shot, the Batmobile has instantly turned itself around and is facing right. Its turntable (which was actually pushed manually by stagehands under the platform) didn't work quite that fast. (00:18:05)
Continuity mistake: At the very end of the episode, when Batman, Robin, and Batgirl find out Joker is released from prison, one shot shows Joker in his usual pink suit. But in the very next shot, his suit is gray.
Louie's Lethal Lilac Time - S3-E18
Character mistake: When Gordon and O'Hara show Barbara the slides of Batman and Robin's previous exploits, the last slide shows the Batmobile being hit with mines. Gordon says they're chasing King Tut, but it's actually from Catwoman's "Better Luck Next Time".
Visible crew/equipment: At the Gotham City Opera House, after the Terrific Trio have taken care of Shame and his men, Calamity Jan and Frontier Fanny show up and spray the heroes with fear gas. When Shame and his gang walk over to Batman, Robin, and Batgirl, a few chalk T-marks are visible on the floor where they will stand. (00:17:45)
Surf's Up! Joker's Under! - S3-E10
Revealing mistake: While Batman and Robin are being processed into the foam surfboard blanks, they are lying on two wood workbenches. When Riptide and Wipeout begin adding the coat of resin to both foam blanks, just as Riptide announces both blanks are smoking, we can see under Robin's wood workbench the fallen wired smoking apparatus used in the stunt. (00:13:05)
The Entrancing Dr. Cassandra - S3-E25
Visible crew/equipment: While Batman and Robin are at GCPD, Batman decides to use the library to research occult sciences, and when it cuts to Cassandra and Cabala returning to their hideout they walk over to the table, and behind them we can see the chalk marks on the floor by the door, where they previously stood. (00:05:15)
The Great Train Robbery (2) - S3-E22
Revealing mistake: At the Batcave, when Batman programs the skywriter drone and switches it on, the two stunt wires are visible as it heads out of the Batcave. (00:15:40)