A Barton Street PC is stabbed when he pursues two robbery suspects into Sun Hill. A black youth, identified as Mark Okin, is found bashed and unconscious at about the same time. PC Jim Carver is assigned to the Okin family in his new role as Family Liaison Officer, but further investigation by CID makes Mark a suspect in PC Brennan's stabbing. Carver is horrified when DS Daly wants him to use his position of trust with the Okin family to collect evidence against Mark. (thetvdb.com)