Some kids do a spell in a church it burns down a girl named Karen is never found years later as a rumor story spreads some kids recreate the spell in the old church with another girl in the middle of the circle when they push her out of the way there is Karen she is back the same age as when she left

The Watcher in the Woods (1980)

The Watcher in the Woods - Wikipedia, the free encyclopedia

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A man named John explains that Karen did disappear but has not died. He tells her that, in a seance-like ceremony, Karen disappeared after lightning struck the tower and a bell fell on top of her. They find out that the disappearance of Karen is linked to a solar eclipse. Jan figures out she needs to repeat the sequence through the strange possession of Ellie.