Her Frozen Heart by Stacy Green

The girl’s pretty face was relaxed, snowflakes settling on her cheeks as they began to fall over the quiet frozen lake where she’d been found. She could have been sleeping… but her empty eyes and the blooming bruises around her neck told a different story…
When Special Agent Nikki Hunt receives a call on Christmas Day, she knows it can’t be good news. Seventeen-year-old missing teenager Kesha Williams has at last been found… her body floating in an icy forest lake, miles from her hometown.
As Nikki rushes to the scene, she’s chilled to see the past repeating itself. Kesha disappeared from the mall where Nikki’s own little girl was targeted the year before. With Kesha’s grieving parents desperate for answers and the media out for blood, Nikki promises she’ll find Kesha’s killer no matter what it takes.
Local police are convinced it was Kesha’s boyfriend, who was spotted disappearing from security cameras that day at the mall, but Nikki isn’t so sure. The dense marshes and unstable ground around the crime scene mean it’s nearly inaccessible from the road. Whoever took Kesha is a local, and this probably isn’t his first kill.
Nikki’s worst fears are confirmed when the team find another grave on the shore – a second teenage girl, her body wound in a brightly coloured beach towel. Suddenly on the hunt for a serial killer, Nikki knows that an early break is the key to solving this case. But as the body count rises, will Nikki be able to find Kesha’s killer… or will he find her first?