Season 4: Underage Serena had an almost-relaysh with her boarding school teacher...

Credit: Giovanni Rufino/The CW ©2010 The CW Network

And it landed him in jail! Thanks to Serena’s mom forging S's signature on a affidavit claiming they did it. Then, his sister Juliet (Katie Cassidy) retaliated against S through the first half of Season 4! Whoa. You think Serena’s current schemes as Gossip Girl are of questionable moral code? Think again! Girl’s got some skeletons in that closet alongside her designer duds. Not to mention, she followed one crazy idea with another: deciding to date the wild-eyed (but innocent) former teacher in question, Ben Donovan, after it he was freshly released from the slammer. Yeah, that didn’t work out.

Season 3 Finale: Jenny Humphrey loses her virginity.. to Chuck!

Then this happened. Ughhh. We’re still shaking our heads over this one! Not only did poor, misguided Little J (Taylor Momsen) wind up in the then-creepy arms of her step-brother (sorta) for her, umm, de-flowering, but the word spread just as Chuck (Ed Westwick) was about to propose to Blair (Leighton Meester). And then she broke up with him (duh!) and Dan gave him a knuckle sandwich (double duh!). Cringey? Scandalous? Porly-timed? Oh, yes. Yes, indeed.

Season 3: Dan has a three-way!

Not only was Daniel Humphrey (Penn Badgley) dating a MOVIE STAR (guest star Hilary Duff = love), but he and his ol’ BFF Vanessa (Jessica Szohr) thought it a great idea for all of them to get it on. At the same time. This scandal rocked the Parents Television Council in a BIG way. Remember the ads? “O-M-3”? Genius, as only GG can provide. Sadly, we’d argue, the Dan-Vanessa bond never really was the same again. Awkward!

Season 1: Serena leaves the UES after a dude dies during a drugged-out… orgy.

Remember this one, guys? Ah, the scandal that started it all. The scandal that saw Serena (Blake Lively) returning to the UES in a shadow of mystery and intrigue. Maybe because it didn’t directly impact anyone that we tooootally loved at the time, this zing wasn’t quite as zingy. BUT STILL. Drugs! Sex! Death followed by guilt and shame! This was big enough to drive S outta town… And speaking of that, how about…

Credit: Janet Mayer/Splash News; The CW © The CW Network, LLC.; The CW © The CW Network, LLC.

Back in Gossip Girl Season 5, Episode 20, “Salon of the Dead,” we were lead to believe that Diana Payne (Elizabeth Hurley) was the long-lost mother of Chuck (Ed Westwick) — and the news was broadcast live over the ‘nets for all UES-ers to see... O-M-G! But even more scandalous? That cringe-inducing realization we all had alongside C-Bass... That this news also meant his BFF Nate (Chace Crawford) was doing the nasty with his bio-mama for weeks (or was it months?) leading up to this whole mess! Shudder.

Our question is, was it the most scandalous moment of GG’s history (even though Diana ended up not actually being Chuck's real mama after all)? On a show that’s known for its fabulously outlandish and brash moments, we’ve got a few contenders for the title…

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