Leverage (Harlequin Intrigue Series #1579)

He'd been hired to transport precious cargo—and it put a beautiful twist in his solitary life 

Former operative turned pilot Dylan Branson has one mission: deliver vital codes to Omega Sector before millions of lives are lost. Surprisingly, the codes reside in the photographic memory of Shelby Keelan, a beautiful computer expert who's so far survived two murder attempts. Used to doing things solo, Dylan will get Shelby to Washington, DC, then walk away. So he's stunned to discover she's as much a loner as he is—and how much that appeals to him. Now, with both their lives in danger after his plane is sabotaged midair, Dylan no longer thinks of Shelby as just a job. Or that he'll be able to let her go once it's over.