Continuity mistake: Right at the beginning of the episode a Cadillac Escalade gets stolen. The car is the newest model. The chase begins and the car is a new model right up to a scene when they crash into some other cars. That part was filmed with older model Cadillac. The damage is quite severe, but the chase continues again with the new model that has only one bit of damage - a mirror that has come apart.
Revealing mistake: When Elise calls Navabi's phone, the phone is not in call mode.
Character mistake: After Elizabeth and Alexander Kirk crash-land into the Gulf of Mexico (technically, the Straits of Florida), Lizzie gets on the radio to report mayday, along with their coordinates. She incorrectly states their position with the following statement: "Mayday, mayday. Plane down off the coast of Havana. 23 degrees, 52 minutes north, 82 degrees, 49 minutes south. Mayday, mayday, mayday." Those coordinates specify two different latitudes (one above the equator, and one below), but no longitude! Luckily, she DID say they were off the coast of Havana, so the Coast Guard would be able to deduce the correct coordinates of 23' 52" north, 82' 49" west (not south!). (00:05:45)
Factual error: When the criminals jump into old Jeep Cherokee, the car interior is a Chevrolet Tahoe, and from the outside when driving backwards, the trim is for a Dodge Charger.
Natalie Luca (No. 184) - S4-E12
Continuity mistake: In the scene with Tom, Reddington, Dembe and Agnes; Dembe is playing with Agnes in her cot while Tom and Reddington talk. Dembe later picks up Agnes and puts her on his knee, only for her to return to her cot mere seconds later.
Continuity mistake: The time on Navabi's phone screen jumps from 6:06 to 6:08 in a matter of seconds when she's talking with Elise.
Character mistake: After the seaplane crash lands off the coast of Havana, Elizabeth radios a mayday. However, she broadcasts nonsensical coordinates. The first set she provides is 23°52' north, the second set 82°49' south. These combined coordinates can't possibly plot to any location on earth. The more probable coordinates should've been 23°52' north, 82°49' west. These coordinates would put the plane roughly 57 miles NNW of Havana, Cuba. (00:05:48)
The Architect (No. 107) - S4-E14
Revealing mistake: Aram Mojtabai fires a high-caliber weapon, destroying a vehicle with it. But after the weapon is fired, the projectile is still in it. Instead, the weapon's lower jaw has disappeared. (00:34:35)
Continuity mistake: After the fight at the club, the amount of blood on Liz's chin increases after Emma points it out to her and Liz washes it off in the bathroom.
Continuity mistake: When Emma and Jessica are waiting for the other two, Emma is looking at herself in the broken side mirror, and Jessica is leaning on the hood next to her when the van pulls in. In the next shot, with the van still pulling in, Emma and Jessica are now standing in front of the Cadillac.
Visible crew/equipment: There are two men in the flat near Elizabeth, even though Elizabeth and Mr. Kaplan are alone in the room. (00:18:35)
Other mistake: It shows an eagle-eye view of the downed plane with the pontoons floating separate from the plane; the plane starts to sink more and Agent Keen incorrectly says that one of the pontoons is taking on more water, even though they aren't attached to the plane and keeping it afloat anymore. (00:05:55)
Natalie Luca (No. 184) - S4-E12
Audio problem: At the end of the episode when Reddington goes to see Natalie Luca (behind glass), he tells her that the woman she killed at the massage parlour was an associate of his. When Natalie says "She said if I didn't kill him, she would tell Hawthorne where to find us", her lips don't match what she's saying in the reflection of the glass.
