fully commit himself to sealing Hell over returning to his normal life with Amelia. Around this time, Sam and Dean encounter their time-traveling paternal grandfather Henry Winchester and discover that through him, they are the legacies to an extinct secret society of compilers of supernatural information and artifacts known as the Men of Letters. Although they manage to subdue the demonic Abaddon, who has pursued Henry into the present, their grandfather is killed, leaving Sam and Dean the last link to the Men of Letters. They then inherit the bunker of the Men of Letters as their first real home. Sam completes the second trial – saving an innocent soul (in this case, Bobby) from Hell and sending it to Heaven – in "Taxi Driver" with the help of Benny, who sacrifices himself in the process of guiding Sam and Bobby out of Hell and thus finally causes Sam to admit to Dean that he had been wrong about Benny. Unfortunately, Sam's illness from the trials worsens to the point that Dean temporarily restricts him from hunting out of worry for his condition. Nevertheless, Sam remains determined to finish the trials and seal Hell because, viewing all the times he has failed Dean in the past (such as not looking for him when he was in Purgatory) as his worst sins, he has become obsessed with not letting Dean down anymore. He and Dean attempt to use Abaddon for the third trial, that of restoring a demon's humanity, but she escapes while they are distracted by a call from Crowley, who has begun murdering everyone they've ever saved to force them to call off the trials. After Crowley kills Sam's love interest, Sarah Blake from Season 1's "Provenance", Sam is devastated and briefly contemplates giving in to Crowley's demands, but he and Dean ultimately feign surrender to lure Crowley to them and take him prisoner in the season finale "Sacrifice" so that they can use him for the third trial instead. Sam is on the verge of fully restoring Crowley's humanity when Dean finds out that completing the trials will kill Sam. Although Sam, having fallen into deep guilt and despair due to him feeling as he always let's Dean down, wants to finish the trials anyway, Dean assures him that nothing will ever be more important than him and manages to calm him down. The effects of the trials