Supernatural2005

[Castiel appears, slams Dean against the wall with a hand over his mouth and pulls out a knife. Castiel stares hard at Dean, who nods slightly. Castiel takes his hand off Dean's mouth, bares an arm and cuts himself, uses the blood to draw a sigil on the wall]

Zachariah:
[appearing suddenly] Castiel! Would you mind explaining just what the Hell you're doing? [he advances threateningly; Castiel slams his palm onto the sigil; Zachariah vanishes in a flash of light]

Castiel:
He won't be gone long. We have to find Sam now.

Dean Winchester:
Where is he?

Castiel:
[handing Dean the knife] I don't know, but I know who does. We have to stop him, Dean. From killing Lilith.

Dean Winchester:
But Lilith's gonna break the final seal!

Castiel:
Lilith *is* the final seal! She dies, the End begins!