I feel bad for cheering inappropriately when Bonnie said, "Ohmygod... I'm dead," but it was time. It was like a mercy killing, at this point. Rarely has a character been so essential to one plot line and so unnecessary to all the rest. We've seen photos of Bonnie in next week's graduation episode, but let's remember, with the veil down in the Expression Triangle, she can still be there as a ghost. So she's really dead. Or, she better be. (Does anyone want her to live? Nothing against Kat Graham, who's lovely. But if you answer yes, pitch me Bonnie's next story line.) Let's go back to the start of the hour.
To distract Elena from her mission to kill Katherine, Stefan began to train her in how to kick a cinder block's ass. After she failed to do the number of pull-ups Stefan requested and realized he wasn't going to help her find Katherine, we found out everyone is mailing their graduation announcements. And by everyone, we mean Caroline. Matt has no loved ones left and Elena just has those family friends in Denver. (Could they be a hot couple that's Alaric's age? Will we ever get to meet them?)
Katherine, meanwhile, met creepy Bonnie in the woods where we learned that Bonnie wanted to charge all three points of the Expression Triangle (where the massacres had taken place) and channel the mystical energy from Silas' tombstone. That would drop the veil inside the points of the Triangle just long enough to get what she needs -- which is to contact Qetsiyah and find out how she put Silas down. Katherine tried to walk away, but Bonnie had linked them so that Katherine was on an invisible leash and whatever happened to one of them happened to the other. Bonnie couldn't have Silas getting inside Katherine's head and finding out Bonnie could do the spell whenever she wanted.
Damon and Stefan ended up at the hospital because Sheriff Forbes needed to be brought up to speed on Silas because at least five patients in the hospital had been drained of nearly all their blood. He was fueling up for something, they presumed. Really, they just needed to be with her when Bonnie blew fuses throughout Mystic Falls to get her "charge" (which apparently comes with a lot of wind and bad sound), so she could pinpoint where the power outages originated. Stefan realized they were the points on the Expression Triangle and that Bonnie would probably be trying to do the spell now at its center.
Elena, having informed Rebekah they were no longer friends and Caroline that she wouldn't apologize for being a bitch to her because then she'd have to feel bad about EVERY thing she'd done when her humanity was off, wanted to go searching for Bonnie with Damon. Why? She wanted him to tell her where Katherine is. Damon ultimately did, because she's with Bonnie. Stefan, meanwhile, went inside to look for Bonnie and found Caroline. We didn't know at the time that when Caroline had gone back inside the Grill to call her mother and ask about the outages, Silas had gotten in her mind and told her to repeatedly cut her wrists. They heard a noise in the kitchen -- was that the real Caroline then -- but they saw nothing but water dripping to the tunnels below. They were in the right place, Stefan said, just the wrong level.