From Prussia with Love - S5-E1
Visible crew/equipment: When the German girl asks if she can sit down, whilst in the Trotter's flat, just above her head, a boom mic pops into view.
Visible crew/equipment: When Albert starts singing when he is drunk, a shadow of a boom mic is visible at the top of the screen.
Continuity mistake: When Del asks Lisa how her mum is, he is just about to sit down but in the next shot, he is sat down.
Continuity mistake: When Del & Rodney are talking to Andy on the hill just before Del goes hang-gliding, look at the first shot of Andy. Over his shoulder, the Trotter van is in full view. The shot then turns to Del & Rodney and when it goes back to Andy, there is no van.
From Prussia with Love - S5-E1
Visible crew/equipment: In the pub scene at the start, when the German girl is telling Albert about being a language student, if you look at the very top right of the screen, you can see a boom mic move around a bit and then move away. (00:04:00)
Visible crew/equipment: When Uncle Albert walks round the corner to the manager's office, a camera shadow is seen on his coat. (00:02:20)
Continuity mistake: When the police car drives out of the Nag's Head car park after the two police officers arrested Del, you can see that the bonnet of the car is damaged, but when the car arrives at the police station, there is now no damage to the car.
Revealing mistake: In the bar scene at the start, Del and Rodney are talking to Mike to try to get him to by a computer that doesn't work. The leaflet that Del reads off, is completely blank.
Revealing mistake: When Albert says to Rodney about his date, "Where are you taking her? Scrumping?" As he says that line, look at Del. He mouths them by accident. (00:26:40)
Plot hole: The Trotter's are taken to the office while the supermarket is still open, the office containing the safe. Tender pickups in supermarkets are done throughout the day but how did the cash from the tills at closing reach the safe? It is unlikely that a supermarket would leave large amounts of cash in tills and counter caches. The Trotters were actually in the office as the store closed, as well as Lennox. The safe is far too small. A safe in a large supermarket would contain large bags of change and would have an inner safe for cash bricks. Also, how is it that no other member of staff noticed the situation in the office - such as maybe a member of staff involved in cashing-up tills needing to gain access to the safe? (I work in a supermarket as a Duty Manager).
Chosen answer: An apparent long string of illnesses.