Episode #1.1 - S1-E1
Plot hole: The real culprit pinned the crime on DI Charlie Hulme, but since everything was improvised and acted on the spot, it doesn't explain how could they access Charlie's safety deposit box at the bank stuffing it with incriminating evidence. It is specified through Fidel and Dwayne's dialogue that the box is at the bank, where everyone is required to show identification to get a box and access it, not some anonymous private storage company or a random locker.
Episode #1.1 - S1-E1
Continuity mistake: Richard just closed the shack leaving the pet lizard behind, and is talking to the Commissioner who roped him into staying. Fidel and Dwayne are looking at them; the lighting in close-up differs noticeably from the wider angle (check out of the shadow on Dwayne's arm and on the wall). (00:50:35)
Episode #1.1 - S1-E1
Continuity mistake: DI Richard Poole is in front of the panic room, explaining how the murder happened. He is holding two evidence bags; the fact that the one with the .22 gun changes position between shots several times is made more obvious by the fact that the tag is visible, and each time Richard's fingers are covering different letters. (00:44:20)
Episode #1.1 - S1-E1
Continuity mistake: The 'cleaning lady' hands Richard a used paper tissue. In the close-up of her hand he is picking it up by a messy, crumpled part, but in the next shot Ben Miller is holding it by a side pretty much straight. (00:19:25)
Episode #1.1 - S1-E1
Continuity mistake: In the opening, two men (one turning out to be future longest serving original cast member, Danny John-Jules) are playing one-to-one basketball. A couple guys are mending nets just by the hoop...but are gone right away in the faraway shot. (00:00:15)
Episode #1.1 - S1-E1
Continuity mistake: Following James Lavender to the beach, Richard calls him "a little proprietorial", DS Lily Thomson between cuts has alternately her right hand on her hip or not. (00:14:00)
Episode #1.1 - S1-E1
Continuity mistake: Sgt. Lily Thomson drives detective inspector Poole to the beach shack. In the opening wide shot she has her left hand on the steering wheel, but in the closer angles the hand at 12 o'clock is the right hand instead. (00:09:10)
Answer: There's probably no particular reason. Sets and props on long-running TV shows often change as needed and for various reasons throughout a series run.
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