Are you partial to thriller and suspense novels? If so, you’re in luck! There are plenty of great detective book series for adults that are sure to keep you engaged and on the edge of your seat. Here are some of the best detective book series for adults that you should definitely check out:

1. The Harry Bosch Series by Michael Connelly
   This series follows LAPD detective Harry Bosch as he solves crimes and investigates murders in Los Angeles.
2. The Alex Cross Series by James Patterson
   This long-running series follows detective Alex Cross as he investigates a variety of crimes and murders in Washington, D.C. and beyond.
3. The Cormoran Strike Series by Robert Galbraith (J.K. Rowling)
   This series follows private investigator Cormoran Strike as he solves complex cases in London and beyond.
4. The Elvis Cole and Joe Pike Series by Robert Crais
   This series follows private investigators Elvis Cole and Joe Pike as they solve crimes and investigate mysteries in Los Angeles and beyond.
5. The Inspector Gamache Series by Louise Penny
   This series follows Chief Inspector Armand Gamache as he solves murders and investigates crimes in the picturesque town of Three Pines, Quebec.
6. The Easy Rawlins Series by Walter Mosley
   This series follows private investigator Easy Rawlins as he investigates crimes and solves mysteries in Los Angeles in the 1940s and 1950s.
7. The Kinsey Millhone Series by Sue Grafton
   This long-running series follows private investigator Kinsey Millhone as she investigates a variety of crimes and murders in Santa Teresa, California.
8. The Dave Robicheaux Series by James Lee Burke
   This series follows detective Dave Robicheaux as he solves crimes and investigates murders in New Orleans and the surrounding areas.
9. The Inspector Lynley Series by Elizabeth George
   This series follows Inspector Thomas Lynley and his partner Detective Sergeant Barbara Havers as they solve murders and investigate crimes in England.
10. The Peter Grant Series by Ben Aaronovitch
    This series follows detective Peter Grant as he investigates supernatural crimes and mysteries in London.

In conclusion, there are many great detective book series for adults out there that can satisfy your appetite for mystery and suspense. Whether you prefer classic mysteries or modern thrillers, there is something out there for every adult reader. So why not pick up one of these series and start solving crimes today?