Credit: Bob Mahoney/The CW ©2011 The CW Network, LLC Photo: Katherine and Elijah Attend a Ball in Season 2, Episode 19: "Klaus"

We love those moments on The Vampire Diaries that make us gasp, pause, and rewind — and Episode 17, “Know Thy Enemy,” was chock full of them. Here are the five scenes that left us with our jaws agape this week.

5. The truth breaks Aunt Jenna.
When Klaus-possessed Alaric lunged at Aunt Jenna with a knife and Stefan vamped out, smashing him into the wall, Elena’s official guardian finally got a clue that something wasn’t quite right in Mystic Falls. But when Klaus/Alaric dared Stefan to stab him, saying, “If you kill this body, what’s to stop me from taking Jenna as my next one?” we knew Aunt J would never be the same. Poor, poor Jenna. First she finds out her boyfriend’s dead ex-wife, who happens to be her niece’s birth mother, was alive (sorta). And now this... Talk about a revelation!

4. Damon almost kills Andie.
Emphasis on the word almost. Minutes after he refused to apologize to Elijah, the sulking Salvatore returned to his bedroom to find the reporter prancing around in her underwear. “I’m upset. And you know what happens when I’m upset,” Damon said. It was a warning. Andie didn’t heed, even when D grabbed her by the head, growling. “You need to know that someone cares about you,” she said, bravely, stupidly or nobly — we can’t decide. Damon bit her in the neck in a way that usually takes a life. But this time it didn’t. He didn’t. He pulled back and gave her one last chance. “Get out of here before I kill you,” he said. “Just go. Go!” Oh the restraint it took for him to do that. Andie may not realize it, but we do. It’s classic Damon: Progression and regression all at the same time.

3. Damon and Stefan fight.
It was a shoving match, really. But that fact that the Salvatores fought over Elena — again! — is really disconcerting. How many times are these brothers going to trade punches over the teenage girl who’s dead-set on martyring herself? We hope this is the last one. But we fear there are more rumbles to come.

2. Klaus gets his body back.
It takes a full moon, a moonstone, a special dagger, and the might of 100 witches to bring this man down. But, apparently, all it takes to reunite his soul with his body is a kick-butt luggage set, some candles, and a couple of folks mumbling in Latin. It was an anticlimactic moment saved by our concern for Alaric. Remember that look in his eyes? It was flash of recognition that surfaced when his conscious returned. But it only lasted for a moment. “Elena?” he said right before his body collapsed.

1. Klaus is Elijah’s hybrid brother.
When Elijah revealed his unholy family ties we, like Elena, were shocked. And why not? It was a “Luke-I-am-your-father” moment. But, of course, our girl rebounded with élan. “I heard that. I’m still processing,” she said. Ever cool-headed, the original vamp Elijah replied, “I’m a little behind on the times. But I believe the term you’re searching for is OMG.” No kidding. The only thing that could top that confession was a revelation that Klaus was some sort of unstoppable vamp-werewolf hybrid bent on siring an army of genetic freaks. Oh wait. That happened.