The Good Samaritan by John Marrs

She's a friendly voice on the phone. But can you trust her?
The people who call End of the Line need hope. They need reassurance that life is worth living. But some are unlucky enough to get through to Laura. Laura doesn't want them to hope. She wants them to die.
Laura hasn't had it easy: she's survived sickness and a difficult marriage only to find herself heading for forty, unsettled and angry. She doesn't love talking to people worse off than she is. She craves it.
But now someone's on to her—Ryan, whose world falls apart when his pregnant wife ends her life, hand in hand with a stranger. Who was this man, and why did they choose to die together?
The sinister truth is within Ryan's grasp, but he has no idea of the desperate lengths Laura will go to.
Because the best thing about being a Good Samaritan is that you can get away with murder.
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