This week in Mystic Falls, everyone's got a secret. Especially Elena and Jeremy's Uncle John Gilbert, who has come back to town for mysterious reasons. And Stefan, who's jittery from blood detox withdrawals. And -- well, you'll have to keep reading to find out who else is on the hush-hush, whose dirty hookups earn a resounding "Eeeew!" and whose secret we DON'T get to learn as fates collide at the Founder's Day Party.

[Full recap of Thursday (April 15) night's "The Vampire Diaries" after the break...]

It's another day in the Salvatore mansion, where one of the brothers is doing pull-ups and push-ups like there's no tomorrow. It's Stefan who's working out like a fanatic, trying to detox from that horrid human blood. Damon has his doubts about how successful he'll be, because human blood is awesome and so very addictive. He tempts Stefan with his leftover afternoon blood cocktail before retrieving it and drinking it for himself. There's nothing wrong with drinking blood bank blood, Damon insists, but Stefan has his reasons. Stefan lives on a high horse, remember? He refuses to touch the stuff. Damon not so secretly enjoys watching Stefan struggle with his bloodlust.

Sark from "Alias" (David Anders) shows up on the Gilberts' doorstep, which puts a damper on Aunt Jenna's terrific morning. He's Elena and Jeremy's Uncle John Gilbert! He's back for who knows how long for unexplained reasons since bouncing after their parents' death, though part of the reason Jenna's not happy to see him is that he's come back to prevent her from selling her brother-in-law's old office to Pearl.

At school, Matt thanks Elena for being there for him after the recent Vicki news. Elsewhere, Jeremy and Tyler also sit together, united in their common Vicki nostalgia. Jeremy questions the coroner's report of Vicki's death, which claims she OD'ed by herself in the woods. Jeremy seems to be the only person who suspects otherwise.

Meanwhile, the town's vampire hunting founders' council calls a meeting. Damon's apparently a new member, brought in by Caroline's mom, Sheriff Forbes. And hey, Uncle John's also there, because he's been a longtime member repping the Gilbert family! Uncle John warns the group that a recent rash of blood bank break-ins means their vampire problem isn't over.

After their renegade rescue mission last week, Alaric is comfortable enough with Elena to alert her to Jeremy's recent interest in vampires. He also questions how she lives with the knowledge and further, how she can keep dating Stefan knowing what he really is. Alaric suggests that Stefan, good guy that he is, is still a vampire at heart. Elena insists he would never hurt her.

At dinner, Uncle John talks to Jeremy about the Gilbert family obligation that calls for them to attend the Founder's Party. Aunt Jenna reveals that since she's related on their mother's side she's not technically a Gilbert, so she never understood the whole heritage thing. Uncle John reveals that the reason Jenna's such a bitch to him is that they used to sleep together. Eeeew!

Elena tells Stefan that she's tired of all the secrets that abound in Mystic Falls -- Jeremy's clandestine vampire obsession, the whole "vampires really exist" thing, and her adoption, which she still hasn't revealed to Jeremy. Oh, and there's also the fact that Stefan is totally hiding his uncontrollable lust for human blood. He's been staying away for a few days but claims the evil vampire thing has pretty much cleared up, so they begin making out. As things get hot and heavy and tumbly in the sheets, Stefan gets increasingly rough and his vampire face comes out against his will. He throws himself off of Elena and pins himself the wall of her bedroom -- JUST LIKE EDWARD DID IN TWILIGHT! Only, you know… slightly less silly looking. (Which begs the question: Homage or satire?)

After Stefan's unsexy outburst, Elena calls Damon for back-up. He informs her about Uncle John's involvement with the Founder's Council, which is just one more thing for them all to deal with. Elena's got bigger fish to fry; she wants to know how much longer Stefan's going to be all aggro, probably because she's in desperate need of a good make-out sesh that won't get her killed. Damon suggests that Stefan is finally returning to his real self, something closer to Damon's killer vampire than the pacifist he wants desperately to be. Back home, Stefan chugs liquor in an attempt to stave off his hunger.

Elena knocks on Jeremy's door. She wants to talk, so they go on a walk and she tells him she was adopted. He takes it pretty well, considering. In fact, there's never been a "Guess what? I'm adopted!" conversation easier than this. She brings up Alaric and asks why Jeremy's all into vampires, but he deflects the question, joking that maybe he's just another in a long line of loony Gilbert men.

Cut to the Founder's Day 150th Anniversary party where the Salvatore brothers are in the house! Damon's all about socializing but Stefan's struggling; he starts binge drinking to curb his hunger. Tyler and Mayor Lockwood greet Matt and his MILF Kelly, who are still grieving over Vicki. Tyler steals a bottle of liquor and he and Matt get the party started like proper high school jock BFFs. Elena arrives to find Stefan tipsy, which is kind of cute and slightly alarming. Cute, because Drunk Stefan totally likes to dance! Drunk Stefan bribes the DJ to start playing Phoenix and starts cutting a rug with Matt's mom in the middle of the party. Elena looks on, wondering what alien vampire has taken over Stefan's body. Damon is amused.

Alaric finds Aunt Jenna at the party. He's been MIA -- and really, since she always brings up his (un)dead wife whenever they get together, why wouldn't he be? -- but he's finally ready to get a drink with her. Matt asks Elena to dance while Damon flirts with Caroline's mom, who looks rather MILFy herself out of uniform. They talk about how much Damon fits in with the rest of the vampire hunting town council. Jeremy comes by to question Vicki's death, totally ruining Damon and Sheriff Forbes's almost-icky vibe.

Stefan dances Elena into a super rude guy who insults Elena's dancing (HA!), and Stefan vampire mojos him into apologizing. Elena's concerned by Stefan's mounting aggression, and goes to Damon with her concerns. Meanwhile, Damon's concerned that Jeremy's been asking around more about Vicki's suspicious death instead of letting her memory slip away in a respectable torrent of slanderous drug use accusations.

Also acting suspicious are Tyler and Matt's MILF, who share a clandestine drink…

And Uncle John, who introduces himself to Damon outside. They interrogate each other and exchange small talk about Mystic Falls's vampire problem and about Mystic Falls's history circa 1864, when a crapload of vampires were locked away underground to rot for eternity. John tells Damon he knows he was the one who unlocked the vampire tomb, revealing that he also knows he's a vampire. Damon walks away to avoid a confrontation, thinks twice, and speed-walks back to Uncle John. He breaks his neck and throws him over the balcony before returning to the party.

Jeremy stares into a fireplace in quiet contemplation when Elena walks in. Jeremy insists that Vicki was killed and buried by someone and is hell bent on uncovering the truth. Elena slips up and mentions it could have been "something" that killed Vicki, leading Jeremy to suspect that Elena is hiding information.

Outside the party, Tyler and Matt's mom talk about Vicki. He feels bad for mistreating her while she was alive, but Kelly doesn't seem to mind that he totally treated her junkie daughter like trash; she's just glad to have someone to talk to at the party. Are they flirting? I think so. Eeew!

Meanwhile, a tipsy Matt semi-flirts with Elena. They go outside for some air, where they spy Tyler and Matt's MILF totally making out. Matt punches Tyler in anger, and they fight; Tyler's aggression veers out of control, and when Alaric pulls him off of Matt, he sees something… strange in Tyler's face. Matt's face is a bloody pulp, but he probably doesn't mind all that much since Elena is tending to him. Caroline, who doesn’t show up in this episode, is somewhere weeping into her Haagen Dazs.

Damon finds Stefan to tell him the town council's sniffing out vampires again, and to break the even worse news that he just killed Uncle John. Damon steps out and Stefan starts to follow, until he senses something. An invisible beacon pulls him through the halls until he finds Matt's mom crying in a corner. In a trance, Stefan is mesmerized by a streak of blood on her forehead. Stefan snaps out of it in time to collect himself and get out of the house, but outside his hunger takes over and he licks the blood off his fingers.

Inside, Damon is once again enjoying the party. His face falls when, across the crowded room, he spies Uncle John -- alive and well, as if nothing had happened. Mayor Lockwood gathers the revelers for an announcement. In honor of the 150th birthday of Mystic Falls, he invites an old upstanding member of the community -- Uncle John -- to ring the charter bell. Uncle John speechifies about the town being like family, where they protect each other. Damon whispers to Alaric that he and Uncle John have the same undead ring. Damon wonders if Isobel, who gave Alaric his ring, was involved with Uncle John -- who happened to be present at Elena's birth 17 years ago.

Outside, Stefan is accosted by the rude jerk from the dance floor who tries to pick another fight. But this Stefan is the wrong Stefan to mess with; he crumples the guy's hand with his uber-vampire strength and as the man crawls away in fear Stefan's vampy face comes out.

Back home, Jeremy tears Elena's room apart snooping for something. He finds her journal hidden behind a painting and reads it, learning about the entire history of "The Vampire Diaries" thus far -- including the truth about Vicki and what Damon did to erase his memory. Busted! Elena, meanwhile, finds Stefan's victim outside; he claims he fell on his own and hurt his arm, but Elena suspects otherwise.

Inside the party, Mayor Lockwood confronts Tyler about the fight. Tyler doesn't understand what happened; he thinks he was just drunk and lost control. Mayor Lockwood slaps him for embarrassing the family. Way harsh, man. Even harsher: We don't learn even a smidge about why Tyler went all Jacob Black-in-the-movie-theater crazy, even though we're dying to find out!

Back home, Matt packs a bag to send his mom out of the house. Kelly is a hot mess and apologizes for failing him and Vicki, but Matt tells her to leave by morning. He's right; parents in Mystic Falls tend to be pretty crappy, but Kelly takes the prize for worst mom ever.

As the party ends, Uncle John has an interesting conversation with Alaric and Damon. Uncle John reveals he knows way more about them -- and everyone in Mystic Falls, dating back to Damon and Stefan's 19th century roots -- than anyone suspects. Uncle John threatens to tell all if anything happened to him and reveals that he inherited his ring from his family. His brother also had one, but he gave it to Isobel and she gave it to Alaric. John also teases Damon with hidden knowledge of Katherine before taking off, leaving both Damon and Alaric like, WTF??

Elena comes home to find Jeremy, who acts like he didn't just read her diary to find out EVERYTHING that's been going on in Mystic Falls. She goes upstairs and finds a distraught Stefan losing it in her room. He tells her what happened with Matt's mom and the blood and the parking lot jerk, explaining that he didn't feed on him even though he wanted to. Stefan is not taking this withdrawal well. The good boyfriend in him wants to tell her everything, but he also doesn't want her to see him like this. He keeps his distance, afraid of hurting Elena, but she's not scared. She embraces him; they exchange "I love yous." It's sweet. Deep down, aren't we all suckers for vulnerable boys on the verge of a nervous breakdown?

Back home, Stefan finds Damon sipping on a nightcap in worried repose. Damon begins to explain their huge Uncle John problem but is stopped short when he realizes how much Stefan is struggling with his blood lust. He leaves Stefan a glass of blood on the table, which Stefan slowly and reluctantly drinks.

Next week: Stefan still has a monster of a drinking problem, and as Elena competes in the Mystic Falls beauty pageant Damon becomes her go-to Salvatore.