Other mistake: Throughout the episode, Lucifer's car has a California license plate - but that is, just one. He is missing the one in the front. In the following episode the car does have the regular 2 plates, and when he is pulled over at the beginning (and keeps being around cops all the time), nobody raises an eyebrow at the violation of the code.
Continuity mistake: During the scene in the school corridor with Lucifer sitting down and talking to Chloe's daughter, the same extras keep doing erratic back-and-forth for no reason (for instance the girl with a white jacket and pink shoulder bag) or just plain wrong (the kid with the horizontal striped maroon sweater who walks twice past Lucifer early in the convo). (00:24:50 - 00:25:50)
Factual error: The record producer is holding a pistol model 1911 or 1911A1 which is a .45 caliber handgun with a standard magazine capacity of 7 +1 rounds, the +1 being loaded in the chamber, however newer magazines hold 8 +1. Therefore, this handgun can hold a maximum of 9 rounds, however the producer fires 10 shots before Lucifer grabs him. Newer 1911 style pistols are now produced in 9mm which have a greater capacity but the pistol held by the producer was a standard 45 ACP judging by the metal and finish. (00:37:38 - 00:39:18)
Continuity mistake: Lucifer walks down the stairs into 2 Vile's mansion; first person he comes across is carrying a glass, wearing a black T-shirt and grey undershirt sticking out. The guy is walking towards Lucifer as if he were going to use the stairs Lucifer is descending, but just vanishes in the following shot, only to reappear at the next cut, taking the stairs as it seemed bound to happen all along. (00:16:15)
Continuity mistake: When Lucifer talks to the killer in agony in the car wreck, blood streaks change on his face between shots (in particular, he has blood coming from the corner of his moith in the last shot, from the side, but he had none a moment before, in close-ups). (00:09:40)
Continuity mistake: At the beginning of the episode, a cop pulls Lucifer over. The car stops with the front wheels on white road markings. When Lucifer is shown taking off again, the street is just not the same, there's no white horizontal lines, and a manhole appears under the car. (00:02:45)
Answer: Boo Normal and Once Upon a Time were going to be part of season 4, then the show got cancelled (before being picked up elsewhere). As such they were added on to the end of season three as "bonus" episodes, hence the continuity being off. But not really a mistake, just a quirk of broadcasting. Boo Normal was originally going to be between the episodes "High School Poppycock" and "Infernal Guinea Pig" in season 3 before being slated for season 4, presumably because aside from the point you've raised, it was fairly flexible, continuity-wise.
Jon Sandys ★