Cast crossovers between The Big Bang Theory and Young Sheldon that you definitely missed

The Big Bang Theory and Young Sheldon might be decades apart in storyline, but in reality, the two shows are more intertwined than you’d think. While a few actors openly reprise their roles or lend their voices, others quietly show up in new roles or background cameos that fly under the radar.

So, who actually appeared in both shows? Here’s the full rundown of cast crossovers between The Big Bang Theory and Young Sheldon you may have missed or forgotten.

Jim Parsons

via CBS

Let’s start with the obvious: Jim Parsons, the face of The Big Bang Theory, narrates Young Sheldon as the adult version of the title character. He also serves as an executive producer, giving the prequel its signature tone. He finally appeared on-screen, along with co-star Mayim Bialik, in the Young Sheldon finale.

Mayim Bialik

via CBS

In the Young Sheldon season four finale, Amy (voiced by Mayim Bialik) makes a surprise appearance in a narration moment where adult Sheldon reflects on winning the Nobel Prize. She also appears in the show’s finale.

Bob Newhart

via CBS

Comedy legend Bob Newhart played Professor Proton, Sheldon’s childhood hero and science TV host, in both shows. In The Big Bang Theory, he appears as both the real Arthur Jeffries and a ghostly projection in Sheldon’s mind. In Young Sheldon, he reprises the role in a similarly imaginative capacity.

Elon Musk

via CBS

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Vernée Watson

via CBS

Vernée Watson played Nurse Althea in The Big Bang Theory. And in two episodes of Young Sheldon, she played Nurse Robinson.

Iain Armitage, Lance Barber, and Montana Jordan

In a special flash-forward moment during The Big Bang Theory season 12 episode, Sheldon finds an old tape of his younger self, with Iain Armitage (Young Sheldon), Lance Barber (George Sr.), and Montana Jordan (Georgie) appearing in-character via VHS footage. It’s a touching bridge between the two timelines and a rare moment of live-action crossover.

Annie Potts

via CBS

Annie Potts plays Meemaw in Young Sheldon. While Annie Potts never physically appears in The Big Bang Theory, the producers created a voice message from Meemaw for Sheldon and Amy’s wedding. It wasn’t broadcast as part of the episode but was released online as bonus content.

Melissa Tang

via CBS

Melissa Tang played Ms. Fenley, a music teacher, in Young Sheldon. She also appeared as a mom in the episode Georgie and Mandy. But before she joined the prequel, she had a brief guest role in The Big Bang Theory a character named Mandy Chow.

Lance Barber

via CBS

Lance Barber plays George Cooper Sr. in Young Sheldon, but years before, he appeared in The Big Bang Theory as a completely different character: Jimmy Speckerman, Leonard’s high school bully. People were surprised to see the actor return as Sheldon’s father. This is one of the many inconsistencies in Young Sheldon that don’t match The Big Bang Theory.

Octavia Spencer

via CBS

Octavia Spencer appeared in The Big Bang Theory as a DMV employee helping Sheldon get his license (with great patience). She later showed up in Young Sheldon as a professor who briefly mentors Sheldon at East Texas Tech.

Todd Giebenhain

via CBS

In The Big Bang Theory, Todd Giebenhain played Mitch, the super awkward/creepy roommate of comic store clerk Denise. In Young Sheldon, he plays Dennis, the shady guy who sells gambling machines to Meemaw. A blink-and-you-miss-it connection, but a fun bit of crossover trivia nonetheless.

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