Jack Halford announces that he's quitting UCOS. As the team try to figure out why, they receive a case from Whitehall intelligence operative Stephen Fisher concerning an unsolved murder dating back 160 years. While the team reluctantly attempt to solve the case, Jack receives several mysterious phone calls from someone named Elizabeth Green. Though Gerry, Sandra and Brian originally suspect the caller is Jack's girlfriend, further digging from Brian reveals that Jack has in fact been contact with the Elizabeth Green Hospice, in connection with a terminal illness.