Saved by the Bell Reunion: Behind-the-Scenes Photos From The Tonight Show With Jimmy Fallon

Saved By The Bell cast
The Saved by the Bell cast reunited for an epic Bayside High School throwback during The Tonight Show With Jimmy Fallon on Wednesday, Feb. 4 -- browse through behind-the-scenes photos! Douglas Gorenstein/NBC/NBCU Photo Bank via Getty Images

Class is back in session! The gang from Saved by the Bell's Bayside High School came together once again for an amazing, nostalgia-filled reunion skit during The Tonight Show With Jimmy Fallon on Wednesday, Feb. 4. The former costars shared behind-the-scenes photos and seemed just as "excited!" as ever to don their mom jeans, cheerleading uniform, and more.

Before and after the big reveal, series stars Mark-Paul Gosselaar (Zack Morris), Tiffani Thiessen (Kelly Kapowski), Elizabeth Berkley (Jessie Spano), and Mario Lopez (A.C. Slater) posted dressing room and on-set photos.

"This is gonna be BIG! Tonight on @jimmyfallon Bringing some of my friends along. Don't miss it," Gosselaar, 40, captioned an Instagram pic of himself dressed in his faded jeans and squeaky clean white sneakers. (Bleached blonde hair, too!)

#zackandkelly together with @jimmyfallon on @fallontonight @mpg #reunion #25yearslater #sbtb

A photo posted by Tiffani Thiessen (@tathiessen) on Feb 4, 2015 at 8:05pm PST

"If you enjoyed the #SBTB reunion, this is the man who wrote the skit @mikedicenzo He deserves all the credit. Thanks Deetch & @jimmyfallon," he later tweeted. "Thank you for all the love and support. I'm so happy you enjoyed tonight. Let's do it again sometime. Good night."

Gosselaar reunited with his on-screen high school sweetheart Thiessen, whose real-life pregnancy was written into the script. (Zack and Kelly forever!) "#zackandkelly together with @jimmyfallon on @fallontonight @mpg #reunion #25yearslater #sbtb," the 41-year-old captioned a sweet Instagram pic of the two. In a second snapshot, she gave a closer look at her baby bump and maroon and white pom-poms. "Wait…what?????" she teased.

Wait…what????? Tonight on @jimmyfallon

A photo posted by Tiffani Thiessen (@tathiessen) on Feb 4, 2015 at 7:27pm PST

Gosselaar and Thiessen poked fun at their TV alter egos, as did Berkley and Lopez. Their characters Jessie and Slater (who often bickered on the series) rehashed memories about a high school dance, Jessie's "I'm so excited!" caffeine pills episode, and Slater's ballet leotard. And yes, a "bubba" and "mama" were muttered.

"She's baaaaaaaaaack. @jimmyfallon love you!!! @fallontonight. #bayside, we missed you!!! #curlsfordays #browsfordays," Berkley, 42, captioned an Instagram pic of her getting her hair done. In a second shot with Lopez, she added: "Get ready for some #Sbtb togetherness on @jimmyfallon tonight!" After filming, she also posted a pic with longtime pal Gosselaar.

Me and @mpg post #surprise on @fallontonight!! #history #friendsforever ????????????????????????????????

A photo posted by Elizabeth Berkley (@elizberkley) on Feb 4, 2015 at 8:19pm PST

The appearance was memorable for Lopez, too, who personally couldn't believe that his wrestling days happened so long ago. "Whoa… These pics are 25 yrs apart. Damn, I feel old. #OldScoolACSlater #SBTB #AggressiveMullet," he captioned Instagram before-and-after pics. Backstage, the 41-year-old posted two more. "My boy Mark-Paul & I picking up where we left off.." he wrote.

Whoa… These pics are 25 yrs apart. Damn, I feel old #OldScoolACSlater #SBTB #AggressiveMullet

A photo posted by Mario Lopez (@mariolopezextra) on Feb 4, 2015 at 9:21pm PST

The cast and Fallon shared the epic video on Twitter, and retweeted each other's messages. But Gosselaar, perhaps, said it best when he replied to one of the late-night host's comments.

My boy Mark-Paul & I picking up where we left off… #Bayside #TwentyFiveYearsLater #Reunion

A photo posted by Mario Lopez (@mariolopezextra) on Feb 4, 2015 at 7:33pm PST

"FRIENDS FOREVER…" he quipped.

Watch the amazing video (on repeat) above!

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