Titanium Noir, by Nick Harkaway, is a gem.
The protagonist is a detective who works on spec for the cops, investigating a very particular sort of crime: those involving Titans, those rare privileged few who’ve received one or more doses of a medication that rejuvenates their bodies and sends them through a second growth spurt that leads them to tower above the untreated masses.
Harkaway writes in pitch-perfect noir detective prose–like, Chandler and Hammett would have no notes–except without all the cringy racism and misogyny. The SF metaphor is pretty on the nose, but Harkaway explores it in a nuanced, thoughtful fashion. The mystery at the heart of the book is well-handled. And it has a sequel, which I just learned while finding a link for the book!
Recommended.