Before Nightfall by Kat Martin

When her best friend’s son is kidnapped, private detective Lissa Blayne drops everything to focus on the missing boy. Julie and Lissa have been close for years, so when Julie’s friend Colt Wheeler joins the investigation, Lissa bristles at the former ranger’s take-charge attitude. Lissa doesn’t need a man calling the shots, even if there is something about Colt’s protective side that has her tough exterior melting away. As Lissa and Colt take their search on the road, the tension between them slowly morphs into trust and understanding—and they’ll need both in order to outsmart the dangerous abductor they’re tracking. The only thing hotter than their attraction is the heat of the Mexican sun, but this road trip is no vacation…