Generally speaking, multicam TV sitcoms like The Big Bang Theory tend to rely far more heavily on actors sticking to scripts while filming, as opposed to endless takes of ad-libbed jokes and improvised silliness. After all, time is of the essence when series are produced on such tight turnarounds. But exceptions do occur, as it goes, and star Kevin Sussman's quick thinking during one of his early scenes as Stuart helped give his quirky character a far more pronounced presence as time went by. And I'm pretty sure fans everywhere are all the more appreciative for it.
Sussman, who got married in April 2023 to now-wife Addie Hall, previously discussed the way he managed to secure a bigger role in the Big Bang Theory universe, speaking at a Q&A for Roster Con. It all goes back to the moment when the comic book shop owner quietly expressed his still-burning desire for Kaley Cuoco's Penny in the Season 3 episode "The Guitarist Amplification." Here's how he put it:
There was a scene with Penny, and she comes into the comic book store, and she asks me a question. And as she's leaving, which was not in the script, I muttered under my breath, 'I love you.' From that point on is when they sort of caught on to this whole Stuart vibe, where Stuart sort of regresses. Because he started as a normal person, and then he gets more and more desperate in his undying love of Penny.
When Kevin Sussman first joined The Big Bang Theory in Season 2, he enjoyed a two-episode arc involving Stuart going on a couple of dates with Penny, and at least at the time, he was a fairly straightforward and normal dude, at least through the prism of sitcoms. But with that relationship destined to go nowhere, Stuart could have turned into far more of a background character for Sheldon, Howard, Leonard and Raj to say hi to when seeking out back issues.
Thankfully for fans who love when Stuart gets sucked into the plot, it was in Sussman's fourth episode when he brought his under-the-breath adoration into the aforementioned scene with Cuoco, and that pretty much cemented his regular presence within the CBS hit. It just goes to show you: even when your instincts don't seem like they'll be welcomed, it might just land you a bigger role on The Big Bang Theory. That lesson may not be so universally relatable, I guess.
The Big Bang Theory cast and crew have talked in the past about how quickly the writers will converge and correct whenever jokes weren't necessarily landing while filming episodes. As Sussman himself noted in 2019, rather than relying on the actors' off-the-cuff skills, the writers were known to handle joke substitutions on the spot.
Stuart certainly delivered some awkward moments from one season to the next, but by the end of TBBT's run, the creative team finally cut him some slack by way of giving him career success and a promising love life. With the flagship series having come to a Nobel-honoring conclusion with its series finale in 2019 I feel like more than enough fans out there would love to see a spinoff focusing on Stuart — and not a Young Sheldon prequel — hopefully with other co-stars returning in some capacity.
Kevin Sussman continued to show off his sitcom chops after Big Bang ended by way of reuniting with Mayim Bialik for Call Me Kat. He showed up for two episodes in the Fox sitcom as Zac, but it sadly didn't survive long enough for him to secure a larger role through genius ad-libbing.