When Ollie heads out for a run in the park, the last thing he expects to find is a dead body. But the real shock is that Ollie recognises the man. And somehow, he's connected to Ollie's father ... who vanished ten months ago.

And then he learns that the dead man was a spy.

With everything he thought he knew about his dad now in doubt, there's only one way for Ollie to get answers. He's going to have to solve the murder.

Armed with an old spy kit, a couple of bikes and a drone, Ollie and his friends Ella and George are about to step into a world that is more dangerous than they could ever have imagined ...

From bestselling author Tim Ayliffe comes a children's debut that will have you on the edge of your seat.