Luke, played by Brian Thompson, is a character in the television series Buffy the Vampire Slayer.
Luke is a vampire who is a powerful member of Order of Aurelius. When we meet The Master, he is trapped in the Hellmouth under Sunnydale. He has a once-in-a-century opportunity to escape in a ritual called The Harvest, which calls for him to use the strongest of his brood (Luke) as his "Vessel". The only way to prevent The Master's escape is for Buffy Summers to kill the Vessel.
At the end of "Welcome to the Hellmouth", Luke flings Buffy into a stone coffin and it looks as though he is going to kill her. At the beginning of "The Harvest", she escapes. When Buffy and Luke meet again for a fight to the finish at The Bronze, she defeats him using subterfuge: she breaks a window that had been painted over, admitting the light of a streetlamp, which Luke momentarily mistakes for sunlight, distracting him long enough for Buffy to stake him.