The Big Bang Theory and Young Sheldon Finally Crossed Over, and It Was Really Sweet

After months of speculation, Young Sheldon finally crossed over to The Big Bang Theory, and it was a really sweet and heartfelt moment that felt more like the wholesome prequel than the spikier original show.

In "The VCR Illumination," Sheldon (Jim Parsons) was still reeling from his and Amy's (Mayim Bialik) super-aysmmetry theory being disproven, and had sunk into a deep depression that was causing him to reevaluate everything in his life (he decided he was "Fine with Flags," so you know he was struggling). To try to lift him out of his funk, Leonard (Johnny Galecki) gave Sheldon back an old VHS tape he was holding onto for him of his younger self (Iain Armitage) giving him a pep talk in case things ever got bad.

"Sheldon," young Sheldon began, "Never forget, no matter how bad things seem, you can always--" It's at this point that young Sheldon was suddenly interrupted by a high school football game. His football coach father (Lance Barber) had taped over his video. This set Sheldon off even worse, and he snapped at Amy, telling her that nothing matters and nothing was ever going to work out.

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Later in the episode, after they had a viking funeral in the bathtub for the super-aysmmetry paper, Sheldon and Amy were watching the rest of the football tape when it cut to the locker room at halftime and George Sr. was giving his players, including George Jr. (Montana Jordan), a pep talk. It was the first time Amy had ever heard George Sr.'s voice.

"I know we're down. By a lot. If I'm being honest with you, we're probably not going to win this one," George Sr. said. "In fact, we're definitely not going to miss this one. We're not going to quit, either. And if we do lose, you need to know that doesn't make you losers. You learn as much about who you are and what you're made of from failing as you do from success. Maybe more. So you can spend the next half feeling sorry for yourselves, or you can get out there and give 'em hell."

Watching his father's encouraging speech from the past awakened something in Sheldon. "I've been acting like the game is over, but its only halftime," he said. "There's a lot more physics left to play."

"Wow, was that your first ever sports metaphor?" Amy asked.

"It was," Sheldon said. "And I think it was a home run. That's two." Look at Big Bang, doing new things as it winds down!

"It's interesting," Sheldon continued. "I've always thought that my father's journey and mine were so different, but he also faced failure and setbacks. Maybe our lives mirrored each other more than I thought."

This inspired Amy, who realized from Sheldon's changing perspective on his father that super-aysmmetry depends on the angle of the beholder. And just like that, the busted theory is resurrected. Sheldon and Amy's Nobel Prize dreams are back on.

"Thanks, Dad," Sheldon said to his father's memory. "We're gonna give 'em hell."

The crossover was slightly surprising and more moving than I expected it would be. Sheldon's changing perspective on his relationship with his late father has been a really lovely emotional throughline since Young Sheldon premiered.

The Big Bang Theory airs Thursdays at 8/7c on CBS.

(Full disclosure: TV Guide is owned by CBS.)

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