I liked this book in the series a bit better, because Lacey found some measure of happiness, albeit brief. While his quarrel with Brandon escalates to include Louisa Brandon, Lacey seems to find a bit more of himself - he seems to be a bit more settled and able to "move on" with his life.The Glass House is a notorious place where only invited men go to slake their lusts. They choose one vice per night - vices are behind the glass windows. The highest bidder gets to decide whether to participate in the vice or watch. While the vices mostly include sex (including sex with underage girls or boys), they also include gambling and drugs.Lacey is roused from his rooms and his musings by his former sergeant, Pomeroy (now part of the Runners), who wants him to identify the body of a young woman just fished from the Thames. Pomeroy believes that the woman is Marianne, Lacey's upstairs neighbor. To Lacey's relief, the woman is not Marianne; the woman is Amelia "Peaches" Chambers - married to a barrister and mistress of a Lord Barbury. Peaches has a room at the Glass House where she meets Barbury for their affair. Peaches is also known to frequent the afternoon gatherings at a Mr. Inglethorpe's home.As usual, Lacey needs help from his friend Grenville, who is not only rich, but welcome in the first circles. Grenville's name and money open any doors, including the Glass House. While there, Lacey discovers a 12-year old girl in the employ of the oily proprietor of the Glass House; Lacey breaks the glass window, grabs the 12-year old, and spirits her away to his friends, the Derwents, who have money, power, and are incorruptible.Lacey also goes to a gathering at Inglethorpe's. Grenville doesn't accompany him, because Inglethorpe is known to prefer both men and women and has made one too many passes at Grenville. At Inglethorpe's, Lacey is surprised to find Mrs. Brekenridge, widow of a corrupt officer part of his previous mystery, and Mrs. Danville, niece of the Derwents. Lacey has had a crush on Mrs. Danville since meeting her, but he's never had much opportunity to talk to her. On this occasion, Inglethorpe's "gatherings" mean that the participants breathe in some sort of "gas", which gives them a feeling of euphoria and well-being. Lacey feels well enough to waltz - something he's not been able to do since his knee was shattered on a mission that his ex-superior, ex-mentor, and ex-friend Brandon sent him on, intending that Lacey should never return. Lacey waltzes with the delightful Mrs. Danville, and under the influence of the gas, they flirt and laugh.Once the gathering is over, however, Mrs. Breckenridge, who's made passes at Lacey before, titillates him by telling him she has a juicy piece of news. Lacey dashes out to follow her, leaving behind his precious walking stick with a sword in the handle. As the gas wears off, Lacey finds his knee hurts worse than ever; Mrs. Breckenridge takes him to her home, where her manservant ministers to Lacey with hot towels, massage, and a special cream to relieve the ache and pain. Lacey ends up spending the night in the guest room, but wakes to find Mrs. Breckenridge slip in beside him. She only lays her head on his shoulder, and Lacey accepts her presence and comfort.But the next day, when Lacey goes to retrieve his walking stick, he discovers Inglethorpe dead - stuck with the sword from his walking stick. Inglethorpe's shirt, vest, and coat are neatly folded on a chair, as if he was expecting a lover. Lacey is nearly arrested for the deed, except he has a solid alibi. But who had his walking stick?As Lacey pursues the murderer, Peaches' lover, Lord Barbury is also killed. And James Denis is involved - as always; Denis doesn't own the Glass House, as Lacey suspected. Rather, Denis wants Lacey to shut it down, since it's owned by a rival.Who killed Peaches, Inglethorpe, and Lord Barbury? Why? What has Mrs. Danbury to do with any of this, since Mrs. Breckenridge swears she saw Mrs. Danbury run after Lacey with this walking stick? And what designs has Mrs. Breckenridge on Lacey - is she just one more person who wants to entrap Lacey?-------------As I said, a more enjoyable book than the other two, if only because Lacey isn't quite as melancholy. He takes some comfort in Mrs. Breckenridge - doesn't fall in love with her, but allows himself to relax and feel.I didn't guess the culprit in this book, which was a nice surprise. As always, these books are well-written, and the characters are very well drawn. You hate the villains and cheer the heroes. There are always enough red herrings and twists to muddy the picture. But enjoyable mysteries, nonetheless.