It seems like every "Lip Sync Battle" keeps topping itself. After The Rock killed it with "Shake It Off" in the premiere and Anne Hathaway came in like a "Wrecking Ball" with a super-method performance, it's hard to imagine anything being better.

I'm here to tell you that Anna Kendrick and John Krasinski's battle is the best of the best, and it's one for the record books.

I was on set when Kendrick and Krasinski — say that five times fast — taped in NYC, and both performers really brought their A-game. Even though no one had as big of a prop as Hathaway, they used backup dancers, shimmery dresses, and surprise guests that will blow you away. The biggest one of all was already revealed in the star-studded promo for the season — Jennifer Lopez during Kendrick's performance of "Booty" — but there are still some behind-the-scenes secrets that you may not see on Thursday's episode.

To prepare you for the epic lip-sync-off, check out nine insider moments that happened during the Krasinski vs. Kendrick battle.

There Was A Lot Of Trash Talk

See these smiles? All fake. No, just kidding, but they one-upped each other with trash talk, especially during commercial breaks. Many times, Krasinski fake-threatened to fire her since they just worked on a movie together that he directed and stars in with Kendrick.

Drinking Was Involved

See the bar behind them? It was empty, and Krasinski tried to make a drink in a red solo cup. Chrissy Teigen, who has a real bar sidestage, saved the day and got them drinks.

Krasinski Messed Up His First Take

There isn't a photo of his first performance yet, but he got so caught up in the moment that he tripped on his mic cord and had to start over. There is also a headset mic involved, FYI.

Emily Blunt Was Supposed to Be There, Too

Kendrick sings "Steal My Girl" about wanting to take away Krasinski's wife, Emily Blunt, and she even had a custom shirt made. Turns out Blunt was going to be there in addition to J.Lo, but she was filming in another country.

Some of Their Banter Was About Brownies

When Kendrick was taking a long time to get ready, host LL Cool J and Krasinski joked that she was back there baking brownies. Special brownies, as they suggested. That was not the case, and they were both floored when she did emerge for "Booty."

Krasinski Is a Huge John Legend Fan

Every commercial break, Krasinski would start singing, "We're just ordinary people..." until Teigen had Legend come out to meet him. Legend proceeded to serenade the crowd with "Ordinary People," and Krasinski nearly fell off his stool.

A Fan Serenaded Krasinski

During the long break while everyone waited for Kendrick to come out for her second performance, the warm-up comedian asked people in the audience to sing. One young woman belted out "Listen" from "Dreamgirls" and wowed Krasinski so much that he got her email to contact her after the show. Get it, girl.

It Was LL Cool J's Birthday and His Mom Was There

I was sitting right behind LL Cool J's mom — by the way, his real name is James Todd Smith — and I watched her cry as the crowd sang happy birthday to her. He's a mama's boy, and it's adorable.

Krasinski Was Baffled By How Sexy Kendrick Was

After Kendrick killed it with her booty-popping moves while wearing a low-cut jumpsuit, Krasinski's jaw was on the floor. He lamented how weird it was to see her so sexual, since he knows her for being so sweet. Also, there's such a crazy height difference between them. Even in sneaker wedges, Krasinski has more than a foot on Kendrick.