April in Florida and Ben O'Keeffe is enjoying balmy temperatures, working the last few days of a six-month stint with her old law firm.

A week later she returns to Glendara, Inishowen where a charity cycle race is taking place. But it starts to rain, causing the cyclists to postpone the start of their event and stay overnight in the town. But the rain doesn't stop; it increases to become relentless, torrential.

In the middle of the night Sergeant Tom Molloy is called out to Mamore Gap, where a body, dislodged from a high bank by the heavy rain, has fallen onto the vet's jeep. It is identified as Bob Jameson, a well-known local charities boss, and the organiser of the cycling event. Stunned, the GP confirms that the man has suffered a snakebite.

Terrible weather persists and soon bridges are down and roads are impassable. Glendara is completely cut off, with a killer at the heart of the community. Who is responsible for Bob Jameson's death? One of the strangers in town or someone closer to home? It's left to Molloy, with Ben's assistance, to find out what is going on.