Amid the sprawl of the crime fiction genre, Tana French has mapped out a subcategory in which the detectives get emotionally involved in their cases and things blow up in their faces. In French's Ireland, just as in the real one, the cops may get their man, and they may not; a good yarn is a good yarn either way.

In The Likeness, just as in her first book, In the Woods, the particulars of an unusual murder draw a detective in so closely that solving the case becomes far trickier than the police might have imagined. Here, our heroine and narrator is Cassie Maddox, erstwhile partner of the last book's Detective Rob Ryan. In the aftermath of that book's harrowing events, Cassie is off the Murder squad and working Domestic Violence. (The traumatized Rob is out of the picture). But Cassie's old line of work beckons when the body of a young woman turns up - a woman who not only looks just like Cassie, but had adopted the identity of Lexie Madison, a fictional junkie Cassie had "played" during an undercover operation years before.

Cooking up a story that the victim actually survived her stabbing, Cassie's manipulative former Undercover boss convinces her (with the very reluctant OK of her Murder-squad boyfriend, the devoted Sam) to enter the bosom of the "Lexie"'s old life, specifically the academic circle of her eccentric housemates, and pretend to be the recovering victim while trying to suss out what happened to the murdered imposter.

Preposterous? Pretty much. But once we've bought in to the premise (and plowed through a rather too long set-up), French delivers a giddy, suspenseful ride. Is one of the housemates the killer, and if so, how much danger is Cassie in? What will happen if her cover is blown? What weird bond holds the housemates almost cultishly together? Might the killer be one of the locals, whose resentment of Whitethorn House and its owners goes back generations? Or could it be the disappointed relation who wished to inherit the house and turn the property into condos?

Real estate plays a significant role in the plots of both of French's mysteries to date, and that's not a coincidence. She's a keen observer of Ireland's dizzyingly rapid modernization and the painful conflicts that arise between traditional interests and those fueled by the country's economic boom.