** Denton's indiscretion with Mary. Was it really an attempted rape or just an experiment to see how a servant girl would react to such a thing?
** Likewise the way Denton is treated after [[spoiler: they discover he's an actor]] could be just them annoyed at his deception - or a way of getting back at him for trying to force himself on Mary. Or as Elsie suggests, they may be afraid that he will repeat their gossip about their and their employers' private lives to the Upstairs.
** Constance calling Mary by her first name. Is it as she said, being unable to pronounce her last name? Or is it her way of showing affection for the girl? She's considerably nicer to Mary than she is to a lot of the other aristocrats.
* CounterpartComparison: Constance naturally gets compared with Lady Violet Grantham, given that they're both played by Maggie Smith and ''Series/DowntonAbbey'' was first conceived as a spin-off.
* EnsembleDarkhorse: Elsie is one of the most memorable characters due to being something of a MoralityPet for Sir William, actually calling out the lady of the house despite her position and getting a lot of good lines. She's something of this in-universe too [[spoiler: since the filmmakers decide to take her with them to Los Angeles]].
* FridgeBrilliance: Constance and her spiel about bought marmalade. As she's on an allowance, she's likely not living as luxuriously as some of the others. And rather she can't afford to have servants make marmalade for her from scratch in the kitchen. So she was clearly hoping to enjoy some extra comforts that she couldn't normally afford for her stay.
** Maggie Smith's bluntness is already hilarious but it gets cranked UpToEleven in ''Film/TheBestExoticMarigoldHotel''.
** Mary instantly guesses that [[spoiler: Denton isn't really Scottish]] by his unconvincing accent. Fast forward to the filming of ''Film/NoCountryForOldMen'' where Kelly Macdonald pulled off the Texan accent so convincingly that half the cast thought she was American.
* LoveToHate: Lady Constance is such a DeadpanSnarker that she's hilarious. Half the best lines in the film come from her.
* OneSceneWonder: Inspector Thompson. He's played by Stephen Fry and he's so hilariously incompetent that you forget he only has about ten minutes of screen time.
** The scene where Mrs Wilson meets Robert is a lot more understandable when you know that [[spoiler: he's her long lost son]].
** Denton asking Robert lots of questions. On the first watch he just seems to be making friendly conversation. On the rewatch [[spoiler: he's doing research]].
** When the normally [[TheStoic unflappable]] Mrs. Wilson completely breaks down at the end [[spoiler: because she realizes even though she's protected her son Robert from being arrested for murder, she's lost him forever and will never see him again]].
** Even more touching: it's her [[spoiler: bitter enemy/sister Mrs. Croft comforting her by reminding her that at least he's alive. Realizing that Mrs. Wilson gave up her child because she thought it was best for him, not because she was taking the easy way out for herself, causes Mrs. Croft to forgive her sister after all this time]].
* TheWoobie: Poor Mabel - a lower class girl who was only married for her money. When her new husband discovered the money was all gone, he was furious. He treats her horribly and she's looked down on by the other high society snobs.