The book begins similarly to Little Women (which it predates by about thirty years, having been published in 1837); five young people are sitting in a garden planning their castles in the air. There is a servant named Lavinia (although misnamed Alice for the entire first chapter, which is very confusing), Lady Marchmont - newly married into money and a title (but not love), Walter - a poor writer who is in love with Ethel Churchill (the virtuous, natural beauty) who is in turn in love with (and is loved back by) a young nobleman named Norbourne. The story follows the events of their lives and the twists and turns that bring them together and separate them.
Norbourne loves Ethel, but when he returns home his uncle demands that he marry his sickly first cousin, Constance, who has loved him since childhood. At first he firmly refuses, but his mother reveals to him that she and his father were not legally married, though they were married in the eyes of God, making Norbourne a bastard. His uncle will reveal this circumstance if Norbourne chooses not to marry Constance, and his mother will die of shame. Norbourne loves his mother more than anyone else in the world, so he agrees to marry Constance. Since he hasn't bothered to write to Ethel for over four months, overhearing news of his marriage comes as a bit of a shock to her.
It also comes as a shock to Lady Marchmont, who summarily snubs Norbourne at a party, inducing Constance to falsely conclude that Norbourne and Lady Marchmont had broken off a love affair before her marriage to Norbourne. Laboring under this delusion, she grows more and more sickly, until finally Lady Marchmont figures it out and sets her straight and the two, despite all odds, become best friends.
In the meantime, Walter the Poor Writer, who still loves Ethel Churchill, goes to the city to make his fortune and ends up becoming a hack writer and a playwright for actors like Booth. As fate would have it, Lavinia (who leaves Ethel somewhat cold-heartedly) has become an actress and is still in love with Walter. But Lavinia, being the only person with sense in this novel, is smart enough not to pine away for him and instead does everything she can (and I do mean everything) to get both of them to the big time. And with some moxy, she succeeds.
Meanwhile, Ethel goes into a decline, but fortunately for all in involved, Constance succumbs to her poor disposition and follows her sisters into an early grave. Feeling a bit guilty about having forced his nephew to marry against his will, Lord Norbourne decides to let Nourbourne Jr. marry that girl he was so ga-ga about before. Where is Ethel? Just so happens she's come to London, not on holiday, but as a prisoner.
Turns out that Ethel's grandmother is a crazy Jacobite radical and has been plotting to overthrow the current monarchy and restore the decendents of James to the throne, where they belong (of course, they'll have to get rid of P.M. Walpole first). Originally her grandmother decided to get Ethel married off to an egocentric Jacobite, but fortunately the English police broke in on the wedding and arrested everyone before this could happen. The down side is that Norbourne, happening through the countryside to see Ethel, sees her getting married and doesn't stay long enough to watch the fiasco arrest.
Ethel doesn't want her grandmother to go to jail, but there's not much she can do. She appeals to her old friend, Lady Marchmont, to help her and together they go to see Robert Walpole and use their feminine wiles to get him to spare Granny. But he has gout and loses his temper - fortunately Uncle Norbourne (who is arguably in love with Lady Marchmont - but who isn't?) convinces the P.M. and granny is put under house-arrest instead.
Then they all decide to go to a party. At this point, Lady Marchmont has realized that life is meaningless unless someone genuinely loves you, but unfortunately she has surrounded herself with fakers and a husband with the brain of a idiotic peacock. He orders her to go to the party, despite knowing that her uncle is ill, and there she meets a young Byron - excuse me! I mean, Sir George - who instantly makes love to her and seems sincere. Is this the true lover she's been searching for all this time?
Her uncle dies, and, leaving without her husband's permission, Marchmont arrives hours too late to tell him how much she's missed him. In a scene worthy of Frankenstein, Marchmont sits in her uncle's laboratory and mixes some interesting stuff together which she then distills into two vials. Eventually Lord Marchmont demands that she return home which she does, vials in tow.
In the meantime, Norbourne has proposed to Ethel who not only turns him down but makes it abundantly clear that she never wants to see him again. (Yay, Ethel!) Norbourne goes into a decline.
Marchmont and Sir George begin an innocent affair (which means no sex), sending letters back and forth. Unbeknownst to Marchmont, these soul piercing letters are actually written by her childhood friend (and first love) Walter the Poor Writer, who has been hired by Sir George by way of his mistress Lavinia to write all of Sir George's love letters since he's a busy (lazy) man and can't keep up with all of them. Walter doesn't know he's writing to Marchmont, but when he finds out, through Lavinia, he decides to end the farce at once.
He finds Marchmont on a particularly bad day. Her husband, his tiny reptile brain finally rousing some suspicion, breaks into her writing desk and finds all of "George's" letters. He will throw her out of the house tomorrow. Walter, not knowing all of this, brings the other false letters to Marchmont and tells her the truth, then leaves.
On his way back, he meets Sir George, tells him what he's done, and challenges him to a duel. Sir George tries to laugh it off since, in his opinion, Walter is not a gentleman, but Sir George's friend backs Walter up and they duel it out. Of course Walter, being only a poor writer and suffering from an advanced case of consumption at this point, loses. Lavinia saves the day with her usual applomb and practicality, and Sir George, receiving a letter from Marchmont, hastens to see her, thinking that maybe at last he will get some.
Marchmont receives him in her bedroom (so things look favorable), but even as she explains that Walter has tried to sabatoge their love with his lies, she shows him something a little weird: her husband lying dead in his bed. Sir George realizes he is dealing with a murderess, but when he tells her she'll hang, she calmly points out that all the odds are against him since it would be far more natural to assume Lord Marchmont had been killed by a jealous lover rather than his own wife. Sir George, terrified, runs from the house.
Once he gets to the park where he fatally wounded Walter, he begins to feel a little weird. He thinks back to that coffee that Marchmont gave him and realizes that he's going to die. In a scene reminscent of a Quentin Terantino film, George dies in an agonizingly drawn-out way while all the furry woodland creatures (I am not making this up) despise and revile him and nature herself applauds his death.
Ethel, on her way to see the dying Walter, is visited by Norbourne's mother who reveals that her son was forced to marry Constance and has always loved Ethel (even though he never bothered to explain anything or talk to her) and is dying for love of her. Ethel, for some reason never fully explained, has a change of heart and says that she will marry Norbourne afterall but she's got to go see Walter before he dies, which will be any minute.
Norbourne just happens to have recovered, so they all go to see Walter. Walter dies happily, though mysteriously uttering a cut-off phrase to Lavinia that leaves the reader wondering what the heck was going on.
Ethel is then called from Walter's bedside to find that Marchmont has gone mad and her hair, once raven black, is now completely white. They put Marchmont (who is never suspected for those double homicides) in an asylum and after they are married Ethel asks Norbourne if she can take Marchmont home with them and treat her like a sister. Norbourne just nods and smiles.
They visit Walter's grave and we learn that Lavinia became a Duchess through the use of her immeasurable [acting] talents.
So there you have it. I loved it, actually. I think it would make an awesome play.