Shadow Line by Declan Rhodes

Two bodyguards. Two reporters. One network that wants them both dead.

The man Dane Fletcher took home from a bar on Salem Street wasn’t supposed to walk back into his life three weeks later — across a conference table, working the other side of the same operation.
Blaise Farrow doesn’t run with a firm. He runs on instinct, proximity, and a read of people that gets too close to be safe. Dane runs on distance, discipline, and a perimeter that holds. The Guardians have just paired them on a job neither can afford to fail.
Two Boston reporters have stumbled into the same story from opposite ends. Wiley Priest has spent two years tracking a domestic extremist network. Stanley Cabot has spent fourteen years inside the rooms where Boston’s oldest families talk. Together they’re a threat someone has decided to eliminate — and the countdown to a private wedding on Martha’s Vineyard is closing fast.
Dane keeps people alive by holding the line. Farrow keeps them alive by crossing it. Every hour the threat sharpens, what’s between them does too — and one wrong call by either man puts a principal in the ground.