Castiel lays his hand on Alastair's forehead, but Alastair is not susceptible to angel pimp hand, which shocks Castiel. Alastair sneers, "Sorry kiddo. Why don't you go run to Daddy?" He punches Castiel in the face and sends him flying to the floor. Alastair straddles Castiel, as Uriel applies the angel pimp hand to the forehead of the white minion. It works on him, but instead of leaving in a cloud of black smoke that drips to the floor like so much vomit, the demon's essence burns out of his eyes and mouth, as though he's being purified with unfiltered sunshine -- from the inside. Throttling Castiel, Alastair chants, "Potestas inferna, me confirma. Potestas inferna, me confirma. Potestas inferna, me confirma." It's been a decade and change since I took any Latin, but I think that's pretty plainly rendered as "Infernal powers strengthen me." That is, he's praying for strength from the powers of Hell.
Dean bashes Alastair upside the head with a crow bar, to get him off Castiel. Be careful what you pray for, when you're praying to the forces of evil. Alastair decides it's time to chew some scenery. "Dean, Dean, Dean. I am so disappointed. You had such...promise." Sam's eyes widen at that.
Alastair strangles Dean and Sam with some evil mojo, while Uriel exorcises the essence from the black minion. Before he's finished, Anna runs over to him and takes back her grace. Uriel shouts, "No!" but she's too quick for him. She throws the vial to the ground, it breaks open, and her grace takes on the form of white smoke. It spills out over the ground and right up into her mouth. I liked these special effects when they were used on Galadriel in The Fellowship of the Ring and weren't contracted on a shoe-string budget. She reels. She rocks. She rolls. She falls to her knees. She's got the fire down below. Oh wait, that was earlier. Now she's got a fire in her belly. She herks. She jerks. And as she rises to her feet, she cries out, "Shut your eyes. Shut your eyes!" Ruby, Dean and Sam do just that. Uriel and Castiel look on in amazement. She screams, "Shut your eyes," and is overwhelmed by a brilliant white light. For just a moment, she looks like Anna. Alastair tries to grab her, but he is consumed as her power manifests in a brilliant white flash. Bye bye, Brando.
When Dean, Sam, and Ruby finally look up, Anna is gone and Castiel and Uriel are still stunned. Dean picks up Ruby's Knife That's Now Just a Knife. "Well, what are you guys waiting for? Go get Anna unless, of course, you're...scared." Oh, Dean.