After a full season of fighting Leviathans, it's time for the Winchesters to throw down for the finale. The episode kicks things off in proper, high-stakes form with a season-spanning recap set to Kansas's "Carry On Wayward Sun;" after that we're back to the present, where Crowley is in negotiations with Dick Roman to sabotage the Winchesters' plan. Crowley promises to give them the wrong blood for their anti-Leviathan weapon, Roman promises him Canada.
When he catches up with Sam and Dean, however, he's perfectly forthright about the planned duplicity. He tosses them a vial of blood, tells them that it's his, and they're left to just trust him. They mix all required blood and bone ingredients, and though there are no magical pyrotechnics, they carry on hoping they have it right.
Roman, meanwhile, is saturating his evil plan with about as much evil as possible: he outlines a plan to kill off skinny people and breed fat ones for food while serving orphan sushi to his board of directors. Prophet Kevin overhears their plot and attempts to make a break for it, but he's caught in the hallway.
Sam and Dean's assault on Roman is delayed by the interference of Bobby, who is clearly going straight into vengeful spirit mode. He finally recognizes that his continued presence isn't doing anyone any favors, and they finally put him to rest.
With all business attended to, they finally launch their assault on Romancorp. Meg takes on security in front, while Sam rescues the prophet Kevin. Dean and Castiel, meanwhile, finally confront Roman face to face. Dean's magic bone doesn't do much to Dick at first, but he has a second bone to catch him off-guard. He thrusts it into Roman's neck and kills him, but he and Castiel are warped into purgatory in the fallout. As the season ends, Dean and Castiel are in a den of vicious monsters eating each other; Sam is quite truly alone.
All in all, this was a wholly satisfying finale for Supernatural's seventh season. Bobby got a bittersweet sendoff, Dick Roman got his comeuppance, and Dean got a hard-core cliffhanger. Supernatural has officially been renewed for an eighth season, so look forward to Dean's adventures in purgatory this fall.
"I'm willing to cordon off, say, Canada."
-- Dick Roman, on what he can offer
"I could steal their cages -- the monkeys -- but where would I put them all?"
-- Castiel, on animal liberation
"Bring breath mints, get it in writing and have a plan for when they screw ya."
-- Dick Roman, on the three rules of contract negotiation
"You got anything to say on the topic of Dicks?"
-- Dean, on Dicks