Why Iain Armitage And Raegan Revord Didn't Watch The Big Bang Theory Before Young Sheldon

"Young Sheldon" expanded on the world of "The Big Bang Theory" by giving fans a look at the childhood of Sheldon Cooper. Originally played by Jim Parsons, the spin-off saw Sheldon played by young actor Iain Armitage. Armitage was just 8 years old when he was cast as Sheldon, which posed one surprising challenge for him — he was too young to have watched "The Big Bang Theory" when he joined its first spin-off. "Well, [The 'Big Bang Theory'] isn't really appropriate for me, plus it's not really aimed at my audience level," he said in an interview with IANS (via Business Standard) in 2018.

Having only watched a few clips of "The Big Bang Theory," Armitage instead got his introduction to Sheldon Cooper directly from Parsons. "Mr. Jim (Parsons) was coaching me so I got the character pretty quickly. Mr. Jim is a very fun guy and very nice," Armitage said of his time working with the original Sheldon.

Armitage wasn't the only "Young Sheldon" cast member who was going in blind. In a 2024 interview with CinemaBlend, Raegan Revord, who played Sheldon's twin sister Missy, admitted she also hadn't seen "The Big Bang Theory" when she was cast — nor had she caught up since working on the spin-off. "When I [first] did the show, I mean, I was 9 years old. 'Big Bang' is not for a 9-year-old, so I've never seen it before, and I actually still haven't seen it. I probably should watch it at some point."

Given the ubiquity of "The Big Bang Theory" and the popularity that earned the sitcom a host of spin-offs -– "Young Sheldon" spawned "Georgie and Mandy's First Marriage," while "Stuart Fails to Save the Universe" is in the works at HBO Max -– it's strange to think that its very first spin-off series featured a principal cast who had never seen an episode. Despite being too young to watch "The Big Bang Theory," the stars of "Young Sheldon" excelled at bringing the series' backstory to life.

Following his casting on "Young Sheldon," Armitage went on to make a cameo appearance in an episode of the final season of "The Big Bang Theory." His version of Sheldon was seen in an old video, being watched by Parsons' Sheldon, in the episode "The VCR Illumination." Revord later reprised her role as Missy in six episodes of "Georgie and Mandy's First Marriage."

Outside the world of "The Big Bang Theory," Armitage has found success as a voice actor, lending his vocal talents to the roles of young Shaggy in "Scoob!" and Chase in "The Paw Patrol Movie." He has also appeared in the first two seasons of the HBO comedy-drama series "Big Little Lies," alongside Hollywood stars such as Reese Witherspoon, Nicole Kidman, and Meryl Streep. Armitage is set to return to the series in its upcoming third season.