Silent Scream - Karen Rose (Minneapolis #2)

Goodreads 4.22

When a teenage girl dies in a suspicious fire, Detective Olivia Sutherland is assigned to track down the arsonist. Then she discovers something more sinister: a vicious blackmailer who preys on young people and murders without hesitation. Making her work even harder is sexy firefighter David Hunter. He's not only sharing the case but sparking memories of their long-ago night of passion, when feelings were left unspoken and hearts were broken.

David has his own ghosts, and a million regrets. But while he and Olivia try to face the wall of pain between them, a diabolical puppet master is pulling strings to make a group of twentysomethings do his bidding. Soon Olivia and David are scouring the city for a calculating criminal who seems tantalizingly close--and is moving in for the kill.