Billy Hargrove
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Stranger Things Character Guide
Billy Hargrove, portrayed by Dacre Montgomery, is a major character of Stranger Things. He served as the tertiary antagonist of the second season and the central antagonist of the third season.
He was the older step-brother of Max Mayfield and was shown to echo the abuse from his father in his behavior toward her and her friends, as well as lashing out at other characters.
Billy was eventually possessed by The Mind Flayer, which used his body to kidnap various Hawkins residents in order to build The Spider Monster. His conscience was unearthed by Eleven, and he sacrifices himself to save her and then he apologized to his stepsister for all of his misdeeds before dying.
He was the older step-brother of Max Mayfield and was shown to echo the abuse from his father in his behavior toward her and her friends, as well as lashing out at other characters.
Billy was eventually possessed by The Mind Flayer, which used his body to kidnap various Hawkins residents in order to build The Spider Monster. His conscience was unearthed by Eleven, and he sacrifices himself to save her and then he apologized to his stepsister for all of his misdeeds before dying.