Question: does chuck bass really die in season 3

Answer: No, In the first episode of season four, we find that Chuck is alive and well, having been rescued by Czech girl, Eva (Clémence Poésy) who has no idea of his wealth or who he is. He creates a fake name and persona as he no longer wants to be the manipulative Chuck Bass. He eventually reveals who he really is and returns to New York City with her, at the request of Blair and Serena. Blair insists she no longer loves him, but still schemes to undermine his new relationship. He eventually falls for one of her schemes and breaks up with Eva. He realizes his mistake and begs her to take him back, but she refuses, saying that he showed his true feelings by continuing to believe Blair over anyone else.