In the pulse-pounding thriller On the Edge, a Spanish subway train operator in Brussels witnesses his estranged son Hugo fall to his death off the edge of a platform. Leo had not seen his son for years, but is spurred to investigate the mysterious circumstances of his passing. He discovers that Hugo was involved in a bloody heist, the discovery of which puts Leo in the crosshairs of the police. Leo’s skills in tracking and apprehending violent criminals, as it turns out, are not those of public transit employee.