The Winner by David Baldacci 

The Dream 
 
She is twenty, beautiful, dirt-poor, and hoping for a better life for her infant daughter when LuAnn Tyler is offered the gift of a lifetime, a $100 million lottery jackpot. All she has to do is change her identity and leave the U.S. forever. 
 
The Killer 
 
It's an offer she dares to refuse...until violence forces her hand and thrusts her into a harrowing game of high-stakes, big-money subterfuge. It's a price she won't fully pay...until she does the unthinkable and breaks the promise that made her rich. 
 
The Winner 
 
For if LuAnn Tyler comes home, she will be pitted against the deadliest contestant of all: the chameleonlike financial mastermind who changed her life. And who can take it away at will... 

On the Edge by Kate Horan  

Desperate people do desperate things... 
 
Sixteen years ago, teenage Maddie Marshall's body was found on a desolate beach near her hometown, Carrinya. Vibrant, feisty Maddie was the only daughter of a high-profile politician. The case was the talk of the town but was ultimately never solved. 
 
Nel Foley, daughter of the town doctor and Maddie's best friend, was the last known person to see her alive, and the Carrinya rumour mill was vicious. Nel fled the town and has never been back. Until now. 
 
Now a 32-year-old city GP, Nel returns after her father's sudden death, determined to get in and out as quickly as possible. Begrudgingly, she agrees to run his clinic for a few weeks, but during that time she meets local mum Sophie Warner and that changes everything. 
 
Sophie's husband Ryan, a prominent local real estate agent, was Maddie's boyfriend and Nel is certain he played a role in her death. When Nel discovers that Ryan is not the loving husband and father that he seems, she decides she must prove what he did all those years ago. But as she starts to unravel the past, she discovers the truth is far more complex than she could have imagined. 

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