Tokyo detective Kenzo Mori is sent to London to find the brother he thought was dead, now reappeared and wanted for a vicious killing that threatens to tear both cities apart.

As the body count rises in Tokyo, an untouchable Mr Abbot tries to force Kenzo out of London – but he can't go home without Yuto, and has begun to form other attachments.

A reunion is not what Kenzo or Yuto had hoped for. Meanwhile, it is time for the truth to come out as a surprise visitor arrives from Tokyo, and Rodney contends with a shock death.

As the Mori brothers end up on opposite sides of a frantic Soho gun battle, Yuto relives the split-second decisions that brought them all to this point.

In the aftermath of the gunfight, Kenzo has a choice to make - send Yuto home to face certain death or allow the war to continue and destroy the city he is duty-bound to protect.

As the Mori family set aside their conflicts to mourn Hotaka's death, it becomes apparent that everyone has their own demons to face, courage to find or decisions to make.

Ian threatens to hand incriminating photos of Yuto to the police, leaving Kenzo and Sarah divided in stopping him and forcing each to confront the mistakes of their past.

When Jiro kidnaps Taki and threatens to throw her from a rooftop, the Mori brothers must decide what they’re willing to sacrifice in order to save her life.