Showing Rain Dogs by Adrian McKinty

Winner of the 2017 Edgar Award (Best Paperback Original)
   
It's just the same things over and again for Sean Duffy. Riot duty. Heartbreak. Cases he can solve but never get to court. But what detective gets two locked room mysteries in one career?
When journalist Lily Bigelow is found dead in the courtyard of Carrickfergus castle, it looks like a suicide. But there are just a few things that bother Duffy enough to keep the case file open. Which is how he finds out that she was working on a devastating investigation of corruption and abuse at the highest levels of power in the UK and beyond.
And so Duffy has two impossible problems on his desk: who killed Lily Bigelow? And what were they trying to hide?
BOOK 5 IN THE DETECTIVE SEAN DUFFY SERIES