→4.16 On The Head Of A Pin
===[[4.16 On The Head Of A Pin]]===
[[image:Supernatural-04x16-OnTheHeadOfAPin.jpg|300px|right|thumb|Alastair being tortured by Dean.]]
Alastair is captured by Castiel and Uriel and imprisoned in a [[devil's trap]], but he refuses to tell them anything about the slain angels. Dean is recruited as an interrogator because he was formerly Alastair's student during his time in Hell. After extensive torture, Alastair breaks free. He almost kills Dean, but is stopped by Castiel, who throws Ruby's knife and embeds it in Alastair's chest. Alastair pulls the knife out and fights Castiel. He manages to trap him against a pillar, and admits that while he is unable to kill the angel, he will send him back to Heaven. Alastair begins to chant, but he is stopped by Sam, who has become strong enough to overpower him with ease. Sam forces Alastair to talk, then kills him via his abilities.
===[[4.21 When The Levee Breaks]]===