Back at Whitmore, Aaron had no idea where Elena was, but that was fine, because the brothers had some bantering to do. Damon told Aaron to watch his tone around Stefan, who was "kind of in the midst of a psychotic break." Damon let it slip that he knew about Katherine. Stefan told Damon he was jealous, but Damon preferred the word "disturbed." Aaron chimed only after he (finally) remembered that he had shot Damon -- okay, so Aaron's not as brilliant as his caretaker. Damon quickly smacked him on the back of the head and gave the poor guy a tip: "Go for the heart next time."
Minutes later, Elena finally figured out where she was. She was in the basement of her dad's clinic! That's why she recognized it. Mental flashback to season 1 when John Gilbert set fire to a handful of tomb vampires (and almost Damon) in that very room. Since then, it had become nothing more than a condemned building in Mystic Falls. Just then, Wes' phone rang. Aaron caught him up on the situation. And despite Wes' belief that Damon was in an "impenetrable and inescapable fortified cell," Aaron assured him he was "in front of me imagining what my kidney would taste like." Wes agreed to meet them in his classroom. Cue Enzo's first yummy appearance! Wes injected the accented hunk with an "insurance policy" to guarantee he would return. Then he gave him a blood bag and told him to go play catch up with Damon. This should be fun.
In the woods, Katherine was working on her handstand -- Nina Dobrev yoga shoutout! -- with Matt, whom she was paying to make her hot again. She wanted to get in shape and prolong "this death thing as long as possible." Matt doubted it would work, but Katherine couldn't hear what he said. She was going deaf. Her entire body was falling apart. And it turned out, she wasn't even being dramatic. Her vision was so blurry that she couldn't see when Nadia joined them. That being said, she could definitely tell when Nadia slapped her across the face for writing that suicide note without saying goodbye.
On the walk to Wes' classroom, Stefan got the background of Damon being a test subject in the '50s. He had donated his body to science "except I was alive and it was against my will." Stefan wanted to know how he'd never heard about it, but Damon stopped him before he could become all "guilt-ridden" Stefan. They were on the outs back then, which they aren't now considering that when Aaron tried to make Damon tell the whole story, Stefan cut him off with "I don't recall saying that you could talk." Damon's smirk? Yep, I love when these brothers work together!
With the boys away, Katherine went to the Salvatore kitchen -- by the way, have we ever seen their kitchen? -- to make a raw kale health shake. Nadia made some remark about how she could see why Katherine would want to kill herself if she were staying here. All I could think was "Girl, you haven't been in the bedrooms." Katherine assured her snarky daughter that suicide was nothing but a moment of weakness. Then she asked her a question, "absentee mother to mildly abusive daughter." Could Katherine be forgiven? Nadia thought so. Also, Nadia had a plan to keep Katherine alive. Now we're talking, Nadia. Make yourself useful.
Also dealing with some parental issues, Elena was having flashbacks to when she was a child and her soccer ball went down into her father's basement. She could hear what sounded like somebody being electrocuted -- a method her father wrote about using -- before she ran back upstairs. Back in the present day, Elena asked Wes how he met her father. Wes talked about her dad working to turn vampire blood into a magical cure all. Wait, isn't it already? Elena asked about Enzo, when Wes informed him that he was off seeing her boy toy.
Oh hey Enzo, looking all cute and sexy in the back of Wes' classroom! Enzo told Damon it had been a while ... too long considering I thought it had been too long since the last time I saw Enzo 10 minutes ago. But that's not important. What is important is that his real name is Lorenzo. Of course it is, because he couldn't get any cuter. He tried to introduce himself to Stefan with a handshake, but Stefan picked up on his brother's vibes and denied him. Now, it was finally time for the story Enzo had been waiting 70 years to tell. He hopped up on Wes' desk and all I could think was, "Why didn't I have a professor who looked like that in college?"
NEXT: Megan's murder is (finally) solved