Factual error: In episode 17 there are some scenes showing sick 4400s all around the world. One of them is being carried into an ambulance car in Frankfurt, Germany. The ambulance car's number plate begins with the letters FM meaning Frankfurt am Main. The correct abbreviation for Frankfurt am Main on German number plates is F - not FM.
Factual error: When Lily and Richard are talking in a coffee shop, a TransLink trolley passes by outside. A TransLink is never seen in Seattle, but it is seen in Vancouver, where the show is filmed.
Continuity mistake: When Top tackles the villain into the water his black jacket has a huge NTSC logo on the back. The show cuts to commercial and when returns the villain and Tom fight in the water however the huge NTSC logo is gone from Tom's jacket. They wrestle under water and the villain floats face down to the surface revealing the back of a black jacket. The show attempts to add tension by tricking the viewer into not knowing if it's Tom or the villain's black jacket. (00:37:05)
The Ballad of Kevin and Tess - S3-E9
Visible crew/equipment: While Kevin, Tess, and Diana are hiding out at the Raja, just as Diana tells Kevin that he's dying, the mic's boom pole hovers at the bottom of the screen. (00:32:50)
Voices Carry - S2-E2
Other mistake: The rear windshield of the car was supposedly shot out, but you can see the defroster lines on the intact rear windshield. When the truck comes up behind them with their high beams on, the driver keeps looking into a non-existent rear view mirror as if they are blinding him. (00:12:45)
Continuity mistake: Richard is attacked in the tent by his buddies since they found a single sheet of photo booth pictures of him kissing a white girl. The main attacker throws the picture on the muddy ground. Richard watches it fall close to the front of his left shoe. However, a camera shot from behind Richard shows the flat sheet of pictures face down and about 6 feet behind Richard on his left side. The following front shot shows Richard leaning a little to his left to pic up the sheet of pictures. There is no way Richard could have leaned over to get it either. He would have needed to stand up and walk 6 feet to get it. Also the photos are now facing upwards and the edge of the sheet has now gained a curved up edge. (00:01:48)
Factual error: Missiles are launched at comet, then after impacting the comet it shows the comet passing the moon. Terrestrial missiles do not have the fuel to reach an object that far in space. The missiles were shown with flame and exhaust indicating they were still in the atmosphere. At the time they stated China launched its missiles the object had a time to impact of 28 minutes and speed of 3000 Km per second. Apollo 11 was going faster and it took 3 days to get to the moon. At 10 seconds to impact the missiles shown were still in the Earth's atmosphere. (00:00:07)
The New and Improved Carl Morrissey - S1-E2
Character mistake: The advertising leaflet for the cemetery misspells it "cemetary" on the front cover.
Character mistake: When Collier is meeting all the 4400s at the reunion, Shawn calls Isabelle Maia by mistake. (00:31:10)
Visible crew/equipment: When Diana confronts Tom Baldwin about being a Marked, when Diana says "You know, you're just so bad at this..." a mic boom enters the shot for several seconds. (00:21:40)
Factual error: The co-ordinates of the comet's landing point are given as 47 north longitude and 122 west latitude, thus giving the latitude and longitude the wrong way round. (00:10:10)
Continuity mistake: In the garden table scene, baby Isabelle is seen alternately playing with a white napkin and sleeping. (00:10:15)