Based on the premise “You can’t teach an old dog new tricks,” this British TV series was once the most watched there. [...] things have changed, and the old Unsolved Crime and Open Case Squad will soon be headed toward its final days. Season 11 features three replacement characters (introduced over the past two seasons as the old-timers left, one by one) who have taken on new dramatic strength in the 10 episodes in this set. The new female squad leader (Tamzin Outhwaite, replacing Amanda Redman) has an inner fire that enables her to fight back against superiors she doesn’t agree with, plus a former husband trying to make her life hell. [...] there’s that intriguing Scottish cop (Denis Lawson, replacing James Bolam), who is constantly in conflict with the one remaining cast member, Dennis Waterman.