Ep 18. Through A Glass, Darkly

Duncan MacLeod's mentor, Darius, who had been beheaded 200 years ago by another immortal, returns to him in a haunting vision while he is on his way to Paris to visit his friend Amy. Darius tells him that his spirit is trapped and begs him to free him. When Duncan reaches Amy's place, he learns that she has become berserk and suffering from terrifying visions, just like he had been. Although he is aware that she must be bonding with an immortal, the source of her visions is unknown to him. He decides to stay with her to protect her against harm and comfort her until they find answers.

Meanwhile, aboard an airplane, Methos gets an unexpected visit from Cassandra, an old friend who is another skilled immortal warrior. She's looking for another immortal, Xavier St. Cloud, who had once shared her bed and betrayed her. Xavier has been rapidly killing immortals, and Cassandra has been hunting him down for years. Together they come up with a plan to take him down and kill him for good, but things don't go as planned when it turns out that Xavier has new alliances.

Back in Paris, Duncan consults with his other immortal friend, Joe, who tells him about something called "the dark quickening," in which the killing tendencies of immortals take over and make them ruthless killers themselves. Joe suspects that Xavier may have undergone the dark quickening, explaining why he is so intent on killing. Meanwhile, Amy's visions are growing stronger - she sees a monk, who appears to be Darius, hanging in a noose. Duncan realizes that they must visit a church where Darius had hidden a relic a long time ago. Amy identifies a silver chalice as the relic that Darius had been protecting.

When they leave the church with the chalice, a group of men tries to steal it from them. They fight them off, but things get more complicated when Xavier appears out of nowhere and begins fighting Duncan. During the fight, Amy touches the chalice and appears to slip into a coma, still experiencing her terrifying visions. Duncan manages to knock out Xavier but is reluctant to kill him, even though he has already killed many immortals. Meanwhile, Methos tracks Xavier down and captures him.

Duncan takes Amy to a monastery where they hope to find people who can help her, with the silver chalice. They discover that the chalice was held by the man who beheaded Darius, and that it was imbued with his dark quickening. Amy's visions had been a warning that Duncan himself was in danger of undergoing this lethal transformation. Cassandra and Methos arrive, and they all work together on stopping the dark quickening's progression.

After some intense and emotional scenes, the group succeeds in dispelling the dark quickening energy from the chalice, and Amy and Duncan are saved. They discover that Xavier had been bonded to another immortal, a beautiful young woman, who had somehow helped him overcome his dark quickening. Cassandra understands that redemption is possible for even the worst of immortals, and leaves in search of her own redemption.

Through a Glass, Darkly is an episode filled with intense plot twists, action, and suspense that all comes together in an emotional and stirring conclusion that will keep viewers on the edge of their seats. The themes in this episode revolve around the strong bonds between immortals, friendship, redemption, and overcoming sinister forces that put the world in chaos. Fans of the Highlander series will enjoy the intriguing characters, action-packed and intense scenes, and a storyline that will keep them glued to their screens.