Accidental Strike Team - Andrew Nelson - Bog

Joe Burnett was living the dream; retired young from the corporate world and volunteering with his local fire brigade.
It didn't last.
First the black summer fires sweep through, then strangers start shooting at him, then he meets the mysterious Jessica. He's barely had time to walk his dog before his safe, ordered world disappears, and he crashes head-on into a merciless international criminal organisation and the corruption it propagates.