Episode #1.4 - S1-E4
Continuity mistake: Thomas and Grace are sharing a drink to celebrate her employment with the Shelbys. Thomas pulls out a cigarette, puts it in his mouth (correctly), and then turns to the camera to reveal a backwards cigarette. (00:43:00)
Episode #1.5 - S1-E5
Continuity mistake: When Tommy enters the office where Grace is working on the books he steps forward, leaving the door open, to draw a black star on her ledger. When he turns to leave the door is shut. (00:03:40)
Answer: There has never been prohibition in England. There are many reasons for running an underground distillery. It would be a way to avoid things like government regulations, safe distilling methods, alcohol content limits, taxation, fix pricing, and so on.
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