Which characters died in Stranger Things season 3? Updated: 7 May 2021, 17:24 STRANGER Things is one of the most popular shows to grace giant streaming platform Netflix. After a compelling teaser clip for season four was released on May 6, 2021, we will take a look the characters whose fate was sealed in the show's third installment. 7 Which characters died in Stranger Things season 3? Billy Hargrove Billy was the first to be possessed by the mind flayer in series three Billy started the mind flayer's reign of terror as he was the first to become possessed in the series' opening episode. He spent the whole series kidnapping people and bringing them to the Mind Flayer to be Flayed.