BTVS: TALES OF THE SLAYERS
Rachel O'Connor used an unorthodox method of vampire slaying, slumming through the bleak streets of New York, pretending to be blind and slaying with pencils. She was recruited by the OSS, a secret agency involved in mystical activities, to pose as a Nazi operative at a hand-off, to obtain a mystical artifact that the Nazis had gotten their hands on. At Penn Station, Rachel met up with the contact, but blew her cover by chewing gum, which high-ranking German spies don't do. Realizing that escape is futile, the operative activates the artifact and releases the hidden evil inside -- a djinn! No match for the djinn physically, Rachel managed to outmaneuver the djinn by tricking it back into its bottle. sing her gum to seal the bottle, she placed it inside a Penn Station locker.
Sixty years later, the locker is opened when it is purchased by the high school in Sunnydale, CA, and the bottle is shattered which released the djinn. The active Slayer of the time, Buffy Summers used her mystical friend, Willow Rosenberg to create a temporal fold to send the Djinn back to 1937, causing history to repeat itself.