Leonard is alone & rootless returning to London after his father's death. He moves in with his distant brother William & his family hoping to renew their friendship but learning to drop his expectations of brotherhood. William is a former lecturer & activist who now runs informal meetings with ex-students. He is defiantly unworldly & forever questioning. When a young student follows William's arguments to a shocking conclusion it appears William has already set his own fate in motion. Against a backdrop of tabloid frenzy Leonard can only watch as William embraces the danger in the only way he knows how which threatens to consume not only himself but his entire family.