Revealing mistake: When Alfred proudly shows the sketch with his joke, the top part of the shower pipe disappears in some frames. (00:03:15)
Character mistake: When Batman gets the information from the computer just in time to wrap up the episode neatly, the computer misspells the word "Professor." (00:19:40)
Continuity mistake: Batman got rid of the two goons through non-lethal falls, and he is about to face Scarecrow. Scarecrow has his escape planned; he has his right hand on a lever by the armrest...or in the next shot, on a lever above him. (00:18:05)
Other mistake: At the beginning of the fundraiser for the university, people drop in a basket cash and cheques. All the bank cheques though have the sum written in the wrong format; for instance "five thousand dollars" is written "5.000.000." (00:12:30)
Continuity mistake: Both Batman and Scarecrow's henchmen are reading the same newspaper, one with a "University Museum Benefit Tonight" headline. The same headline though has a different layout; the words "museum" and "benefit" have bigger spacing in Bruce's copy. (00:10:15)
Continuity mistake: Doctor Long pushes a button on the elevator's board. The key shines bright in close-up, it's not lit in the wider angle. (00:02:30)
Christmas With the Joker - S1-E38
Revealing mistake: Batman and Robin, thanks to the Joker's generous hint, are at the toy factory. In the wide shot just before the phrase "Look sharp, Robin", look at the shadow on the ground; Batman's cape deflates, but the shadow does not move and is still just as wide as it was before. (00:17:10)
Christmas With the Joker - S1-E38
Continuity mistake: The ribbon on top of the big package left by Joker by the antenna is inconsistent in position between shots. (00:12:00)
Christmas With the Joker - S1-E38
Other mistake: The train falls off the cliff, explodes, but during the explosion we see bounce off the flames...the train, perfectly intact, even with the lights on. (00:11:20)
Christmas With the Joker - S1-E38
Continuity mistake: The Joker's goons blew up the bridge, and Joker turns to the three hostages. Bullock's candy cane is facing Summer's, but the Joker put it in his mouth facing the other direction. (00:07:50 - 00:09:40)
Christmas With the Joker - S1-E38
Continuity mistake: Joker puts in the mouth of "the Lawful family" members candy canes that they can't spit away. He puts back in Summer Gleeson's mouth the cane with the hook pointing up, but it points down when he's done with Bullock. (00:07:40)
Christmas With the Joker - S1-E38
Other mistake: Joker hosts the show in front of an audience of plywood mock-up figurines. In the wider views we see next to Gordon... Alfred. That would require Joker to know Batman's secret identity. (00:06:45)
Christmas With the Joker - S1-E38
Continuity mistake: In the scene with the old lady and the lad who brings her the package she dropped, the red stripe on the golden package changed position between shots. (00:03:50)
Christmas With the Joker - S1-E38
Continuity mistake: During the wacky scene of the Joker's escape, the balls on the Christmas tree vanish /change position and size between shots. (00:01:35)
Continuity mistake: In the bat nerds laboratory, Bruce Wayne shows them the tape; his hand suddenly turns between shots. (00:12:55)
Other mistake: When Batman listens to the tape left behind by the security guard (and the police's incredibly sloppy investigation) he presses play and not only the tape is at the right point without him having to rewind, but the recording is much different from the actual events and gives him a convenient abridged version. (00:08:00)
Continuity mistake: Batman goes in detective mode in the room, and scans it for clues. The shattered object on the desk changed size and placement of the pieces. (00:07:50)
Character mistake: When Batman looks up at the computer the data of the burglaries, he says they happened "this week", but the dates are June 28, July 3, and July 13. On the screen there's also a typo; "Buaglary." (00:05:00)
Other mistake: Batman is reading the front page of the newspaper, but in the drawings that follow, the paper is right-most, it opens to the left of the page. Gotham is not in Japan. (00:04:50)
Other mistake: On the police blimp, the scanner/radar screen in close-up has a single white circle, but in the wider angle it's two black circles, which are even hand-drawn and thus not perfect circles. (00:01:30)