When Theo and Jasper smoke Strawberry Cough, the sleeping cat changes its position between every cut without ever waking up.
When Theo is having dinner with Nigel, the wires appear to be missing from Alex's hand. In the next close-up, the wires are back.
When Theo walks past the fugees shortly before he's forced into the van by the Fishes, he's wearing a solid-colored tie, but when the Fishes are questioning him, the tie is striped.
Before getting on the bus, the photo of the "lost dog" is of a Sheltie, and is labeled as such. But when getting on the bus, the dog is actually a Papillon, not a Sheltie.
When Theo has agreed to help the Fishes by getting transit papers for Kee and follows an agent to what turns out to be a meeting with Julian on a Double Decker Bus, the bus he chases and presumably boards is a thinly disguised MCW Metrobus, dating from circa 1982, with characteristic boxy, old-fashioned appearance. However, when we cut to the bus interior, it is that of a Wrightbus Gemini model, dating from 2003 or later - this model is much curvier in shape than the Metrobus. Once Julian and Theo leave the bus, it passes by, and we see that it is indeed now the modern vehicle from which they have alighted, carrying the manufacturer's stylised 'W' moulding on the rear panel.
Immediately after Luke kills the police officers, he drives away, keeping to the right hand side of the road and heading into a blind curve, though they had just passed a phalanx of police cars coming at them on that side of the road.
That is indicative of a driver who isn't used to driving on the left hand side of the road.
That is indicative of a driver who isn't used to driving on the left hand side of the road.
As Theo and Kee ride through the Bexhill Refugee Camp there is graffiti on the wall that reads "Uprising." Above this is an Arabic word that is meant to read "Intifada," Arabic for uprising. However, this word is misspelled.
The car Theo steals was earlier referred to as needing a jump start, requiring an additional battery (and jumper cables). Several people incorrectly claimed this was an incorrect reference, since it actually needed a "push start" or "bump start." However, since the car has a manual transmission, it could (and was) started by popping the clutch while rolling in gear, and therefore was indeed started without the aid of an additional battery.
At both the outer and inner gate of the camp (start and end of bus trip) the bus passes underneath a signpost reading "HOMELAND SECURITY - BEXHILL REFUGEE CAMP". Though located far from one another the signposts look exactly the same - down to every spot and mark of the heavily applied artificial weathering.
When entering Jasper's house for the first time, an obviously retouched photo (with the headline "MI5 DENY INVOLVEMENT IN TORTURE OF PHOTOJOURNALIST") shows Janice Palmer holding a camera with a large lens. The hand holding the weight of the lens shows a right hand but should be a left hand. It is unlikely that she would have a little finger that is longer than her index finger, as shown in the photo.
It shouldn't be possible for Theo (or any other ordinary people) to be drinking coffee or smoking cigarettes; the UK cannot grow tobacco or coffee commercially due to its climate and, in this world, the borders are closed and there are no functioning governments elsewhere that would make such a trade possible.
(at around 29 mins) After the wood ambush when Julian is shot and the police pull the car over, a crew member wearing headphones is seen crouching in the boot of the car behind Theo.
While playing the game where Theo and Julian shoot the ping pong ball into each other's mouths, the camera can be seen as a reflection in the window just as they lean in for the kiss.
When Theo enters the building to find and rescue Kee from the shooting, earplugs can be seen as he climbs the stairs.
After the attack on the Fiat Multipla (carrying Luke, Julian, Theo, Miriam, and Kee), when they stop for the police, just as Theo gets out, out his door you can momentarily see part of the framework for the elaborate roof camera rig. As the view crosses the door pillar it disappears; this is apparently used to transition to another shot.
In the climactic 6-minute battle shot, just before Theo enters the hallway where he finds Kee, the camera is briefly visible in the reflection of a window.
When Theo, Kee and Miriam move between Syd's vehicle and the bus to take them to Bexhill, the M3 motorway is visible at the top right of the frame. This scene was filmed at Chobham test track in Surrey (the control tower for the test track also features prominently here) but traffic on the motorway is visible underneath the bridge which swoops around to the right of the frame.
Just before Theo enters the blown-out apartment building in Bexhill while searching for Kee, there is a London Underground (subway) sign visible.
On the version typically shown by US pay TV, the closed captions indicate that the elderly woman in the fugee camp, who is giving the baby bits of orange, is singing in Romany. In fact, she is clearly singing in Russian. This is confirmed by the old photos in the room, which were obviously taken in Russia/USSR.
As Theo and Kee ride through the Bexhill Refugee Camp, there is graffiti on the wall that reads "Uprising." The Arabic graffiti next to the word "uprising" is a misspelling of "intifadah" ('uprising' in Arabic). It was written with the letter dal instead of dad. The correct spelling of intifadah uses the letter dad; it also ends with a ta marbuta, not an alef.
In the coffee shop the word "cappuccino" is misspelled on the wall. It's missing the third "c".