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After a tweedy British gentleman gets his neck broken by a demon, Giles (Anthony Stewart Head) reveals that he knows the man as Philip Henry (Stuart McLean), an old friend who has a tattoo oddly identical to one on Giles' arm. Soon after, Philip awakens from death, possessed by the demon that killed him, and leaves the morgue. Meanwhile, Giles descends into a state of brooding drunkenness and misses a meeting with Buffy. She discovers Ethan Rayne (Robin Sachs) sneaking about the library, and he informs her about the Mark of Eyghon -- the tattoo on Giles' arm. A reluctant Giles soon reveals that as a young man he rebelled against his Watcher duties and formed a circle with five friends, including Ethan, to dabble in the occult. They summoned the demon Eyghon, who then killed one of them. Moving from victim to victim to stay alive, Eyghon is now attempting to kill everyone bearing his mark. Giles' relationship with Jenny (Robia La Morte) is also endangered as she becomes possessed by Eyghon.