In the 16th episode of The Vampire Diaries season 7, " Days of Future Past ," directed by Ian Somerhalder, Damon’s hesitation to transfer Stefan's scar results in Stefan being trapped in the Phoenix Stone. Following the destruction of the stone by Nora and Mary Louise, the episode concludes with the soul-bearing spirits released and a shocking revelation regarding Matt and Penny. You can find a detailed recap of the episode on Fandom or TV Fanatic . Days of Future Past | The Vampire Diaries Wiki | Fandom