Episode 23 of "Highlander"
s02e01 The Watchers

MacLeod still anxious to get revenge for the death of Darius returns with Richie and Tessa to their old home. There Duncan goes to every bookstore to find information on the book left to him by Darius. He eventually enters the bookstore of Joe Dawson. Joe Dawson wants to buy it but MacLeod turns it down and notices that someone is watching the store. Duncan beats them up and starts interrogating them. Joe tells him that he knows all about Duncan. In the back of the bookstore, Joe tells him about the Watchers and what they do. Duncan at first doesn't believe him but soon does. When MacLeod returns to the antique store, Tessa and Richie are gone.(left because they spotted someone watching them.) MacLeod is jumped by Joe's employee and another person. Duncan beats the person badly and lets the employee go. Convinced that Dawson had something to do with Darius's death, MacLeod follows him to an engagement party for Lynn Horton. There he confronts James Horton(the guy responsible for the death of Darius) and punches him. Dawson returns to the bookstore and is confronted by Duncan. Mac asks where his friends are and Dawson tells him he doesn't know. At Horton's place Joe's employee(also engaged to Lynn Horton) questions James's quest to rid the world of immortals and is pushed over the balcony by James. While consoling his daughter Mac calls him and sets up a meeting. When Horton arrives at the warehouse Dawson confronts him about killing immortals. Mac arrives and Horton comments on how he killed his daughter's fiance. Lynn is there and with Horton distracted Duncan takes the gun from James. Mac puts the gun down and when he walks away, James shoots Duncan in the back. Duncan in turn stabs James with his sword. When Duncan wakes up he is alone. When he goes to th bookstore he finds that all the files on immortals are cleared out. Tessa, Richie, and Duncan walk down the street with no knowledge that they are still being watched.