Captain Aidan O'Brien is a decorated officer of the Royal Irish Regiment. While on a personal mission with his brother to retrieve Michael's would-be mate, Aidan visits an old friend on the local Marine Corps base. Aidan accepts an opportunity to return, to train with the infantry Marines at Camp Lejeune. Alanna Falk is a grad student, working with PTSD patients in a nearby recovery clinic. A few months after the unexpected visit from the O'Brien brothers, Alanna can't seem to get the eldest O'Brien out of her mind. She assumes that she'll never see him again. After all, Aidan is a soldier in the Royal Irish Regiment, living in Belfast. She's living in her best friend's beach house in North Carolina. When Aidan shows up on her beachfront deck unannounced, the fireworks fly...along with a Louisville Slugger that she keeps on hand. Both Aidan and Alanna have their own reasons for being alone. As a friendship blossoms and the attraction grows, each begins to uncover the shadows that haunt the other. Aidan, tormented by dreams of a terrible day in Kabul, Afghanistan, rebuffs Alanna's attempts to offer him counsel. Alanna refuses to open up to anyone about why she keeps a handgun in her desk and a bat within reach. Aidan swore he'd never marry, never put a woman or children through life in the military. But the lovely, Southern beauty challenges his strongest defenses. He comes to realize that Alanna may need him even more than he needs her. Especially as the tide turns and Alanna's secret fears become a very real danger.