Burn - Linda Howard

When Jenner Redwine wins a lottery jackpot things get tough: her father rips her off and disappears; her fortune-hunting boyfriend soon becomes her ex; and friends-turned-freeloaders give her the cold shoulder when she stops paying for everything. Jenner can't imagine finding a place in the world of the wealthy. But now, seven years later, she's rubbing elbows with the privileged, despite the fact she still feels like a party crasher.

When her ally, the shy, kind-hearted heiress Sydney Hazlett, invites her on a charity cruise aboard a luxury liner, Jenner reluctantly agrees, not realising that danger lies ahead. Taken hostage by a menacing stranger, Jenner must cooperate in a mysterious cloak-and-dagger scheme, or else. But as her panic gives way to exhilaration, and fear of her captor turns to fascination, Jenner rediscovers feelings she hasn't had in years - and realises she's found a life worth living. If she survives.