Duncan tries to stop and immortal from his past working as an assassin posing as an acrobat from killing mortals, a performer named Kuyler (Peter Howitt), with a flair for the dramatic and a taste for absinthe. Set in Paris, the episode includes flashbacks to 1783, when Duncan and Kuyler first meet, and to 1980, when Inspector LeBrun (Hugues Leforestier) sees Duncan for the first time, and also when Duncan and Tessa (Alexandra Vandernoot) first meet.
SPOILERS BELOW!!! Do not read further if you have not already seen the episode, as this will reveal plot elements.
Duncan first encounters am employee of Kuyler, who is assisting in assassinating Kuyler's targets. He recognizes the style of the other immortal, who uses dramatic performances and makeup to catch his targets off guard. Duncan feels obligated to locate and stop him, so that more people are not killed, as was the baron he was protecting when he first met Kuyler. LeBron is suspicious of Duncan's involvement, since their first encounter involved this same assassin.