Anne Silvester is Blanche Lundie's governess, and her closest friend. But following an affair with the celebrated amateur sportsman Geoffrey Delamayn, she realises she'll be Defiled Forever unless she can get him to marry her. Since they're in Scotland, it'll be sufficient if they stay at a hotel together and address each other as husband and wife in front of the staff. At the last minute, Geoffrey is called away, and he sends his friend Arnold Brinkworth, Blanche's fiancé, to tell Anne what's happened. In order to keep up appearances, Arnold poses as Anne's husband for the night. Which means that in the eyes of the law, he might — or might not — now be married to Anne.
Since Geoffrey would much rather marry a rich woman than the penniless Anne, it's obviously very much in his interest that Anne should legally be Arnold's wife. But how far will he go to bring that about?
This novel provides examples of:
- Accidental Marriage: Two of them:
- Anne Silvester tries to arrange a private marriage with Geoffrey Delamayn under Scottish law, by having the two of them spend the night as husband and wife in a hotel. At the last minute Geoffrey is called away, and his friend Arnold finds himself having to pose as Anne's husband.
- But before that happened, Geoffrey and Anne wrote to each other expressing their intention to marry. Which means that Anne and Geoffrey were already married before Arnold went to the hotel.
- Altar the Speed: Sir Patrick Lundie, Blanche's uncle, advises that Blanche's marriage to Arnold be brought forward. It's a well-meant suggestion, but the result is that they don't realise Arnold might already be married until too late.
- Babies Ever After: In the final chapter, Blanche is expecting a baby.
- Character Filibuster: Sir Patrick delivers a chapter-long argument against the era's obsession with physical fitness over moral fitness.
- Convenient Miscarriage: Anne, who was pregnant with Geoffrey's child, miscarries at the worst possible moment for her, but at a very convenient moment for the plot.
- Domestic Abuse: Hester Dethridge was repeatedly assaulted by her drunken husband.
- Elective Mute: Hester Dethridge lost the ability to speak following an assault by her abusive husband. She recovered, but following his death at her hands she speaks only to God; everyone else has to make do with gestures and written messages.
- Foolish Sibling, Responsible Sibling: Geoffrey's elder brother Julius is a sensible, dutiful man who tries to do what's right. Geoffrey consults only his own convenience.
- The Gadfly: Sir Patrick.[H]e was socially dreaded for a hatred of modern institutions, which expressed itself in season and out of season, and which always showed the same, fatal knack of hitting smartly on the weakest place.
- Generation Xerox: Geoffrey's father was the lawyer who discovered that Anne's mother wasn't legally married. Now their children are caught in a similar tangle of marriage law.
- Gold Digger: Geoffrey is under orders from his family to marry money.
- Good Smoking, Evil Smoking: Geoffrey and his circle of athletes are all heavy smokers. Though the book was written long before the cancer link was discovered, there's already an awareness that they aren't doing their lungs any favours, as Mr Speedwell the surgeon points out.
- Henpecked Husband: Mr Karnegie, the landlord of the Sheep's Head Hotel, whose wife finds fault with him whatever he does.
- I Have This Friend: Geoffrey asks Sir Patrick for advice on Scottish marriage law, saying it's for a friend. In one sense it is — the friend is Arnold, whose actions may have got him accidentally married to Anne. But he's also asking for personal reasons: if Anne is married to Arnold, that gets her out of Geoffrey's hair.
- I Love You Because I Can't Control You: Mrs Glenarm is smitten with Geoffrey because in matters of athletic training, he's completely immune to her powers of persuasion.
- Jerk Jock: Geoffrey Delamayn — a man whom everybody admires for his physical fitness, overlooking his moral degeneracy. In his Establishing Character Moment, he's told to expect bad news, and is horrified at the thought that his favourite horse may be unwell. The bad news is actually that his father is seriously ill, which he takes far more calmly.
- Kick the Dog: Geoffrey kicks his mother's pet dog hard enough to break its ribs, which illustrates his character splendidly.
- May–December Romance:
- Sir Thomas Lundie's second wife is in her mid-thirties, decades younger than Sir Thomas was.
- Mrs Glenarm, in her early twenties, is the widow of an elderly ironmaster.
- The novel concludes with the marriage of Anne Silvester and Sir Patrick Lundie, although Sir Patrick is decades older.
- Murder the Hypotenuse: Unable to get out of his marriage any other way, Geoffrey decides Anne can't be allowed to live.
- Oh, Crap!:
- When Sir Patrick is shown Anne's correspondence with Geoffrey, he's elated — since Anne and Geoffrey were legally married before the incident at the hotel, Arnold's marriage isn't bigamous. A few seconds later he and Anne realise that's all very well, but it leaves Anne married to Geoffrey, who tried to assault her the last time they met.
- At the conclusion, Lady Lundie is horrified at the news of Sir Patrick's marriage — and that's before she finds out who his new wife is.
- One-Steve Limit: Averted. The novel opens with two school friends, Anne and Blanche. In a series of rapid timeskips they marry, give birth to identically-named daughters, and die. The main plotline then follows the younger Anne and Blanche.
- Poor Communication Kills: Repeatedly. One notable occasion is when Sir Patrick neglects to reply to a letter from Lady Lundie, while at the same time Arnold keeps Blanche out of the loop regarding his possible accidental marriage.
- Rich Bitch: Lady Lundie, Blanche's stepmother and Anne's employer, who takes an increasingly vindictive attitude to both of them.
- Ripped from the Headlines: Reform of marriage law was a hot topic at the time the book was written, and wide-reaching changes were enacted midway through its publication as a serial.
- Sanity Slippage: Geoffrey begins to display worrying mood swings after his near-stroke at the foot race, while Hester Dethridge is tormented by increasing visions of herself committing murder.
- Shotgun Wedding: Anne's attempt to marry Geoffrey is because her affair with him has led to a pregnancy.
- Skewed Priorities: When Geoffrey collapses during a run and it's thought his life is in danger, he has one overriding priority. Not to reconcile with his family, or to bid farewell to the woman he's engaged to, but to settle his gambling debts.
- Taking the Veil: Mrs Glenarm gets neatly tidied away into a convent in the final chapter.
- Women Prefer Strong Men: Geoffrey's physical charms don't go unnoticed by Mrs Glenarm.
