Watch George Clooney's Impressive Glow-Up Throughout the Years

During a visit to 'Jimmy Kimmel Live!' the two took a trip down memory lane.

If there's anyone around here that knows a thing or two about a glow-up, it's George Clooney.

The actor was one of several who stopped by Jimmy Kimmel Live! this week for its 20th anniversary, reminiscing on the history of the series and recreating their entrances as guests on the very first episode.

During Clooney's interview, the pair took a moment to reflect on his appearance throughout the years, with Kimmel pulling out a slew of photos from his adolescence.

They began with what appears to be Clooney's school photo, shortly before high school. His white turtleneck blended in with the white background, he wore a pair of glasses, and his hair was styled in a bowl-ish cut, which Clooney admitted his mother had done herself.

At 15, his hair had grown out in a more stylish shaggy 'do and he had ditched the spectacles, but around the time of picture day he was suffering from Bell's Palsy, a temporary condition resulting in one-sided facial paralysis, so his smile was noticeably crooked, which he jumped in to defend before Kimmel could make fun of him, going on to antagonize the comedian.

"You know what? I didn't have a joke, George, and you've really brought everyone down now," he countered before moving on to the next one.

The next photo, around the age of 17, was in black and white, with his hair clipped much shorter and his grin bright. He donned a snazzy suit for his senior year shot, leading Kimmel to say, "I mean, what a progression this is!"

As Kimmel joked about him cleaning up, Clooney joked, "I had a groomer in high school."

Related: Julia Roberts Plastered Photos of George Clooney on Her Dress in Must-See Look

Fans loved the sweet moment and Clooney's jovial attitude, but overall they found that he really hasn't changed that much at all.

"He looks identical to himself now," one comment read.

"I just keep falling in love with him," said another.

"Love Clooney, such an icon and a class act!!!????????????" another complimented.

"Clooney is a Hollywood icon," declared another, with a third agreeing, "He is the best! ?? love him more every day."