For 12 years, The Big Bang Theory was one of the biggest shows on Earth. It continuously brought high numbers for CBS and made stars out of its seven cast members. The show also received mostly positive reviews, although certain aspects of its humor did receive considerable criticism for much of its run.

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Big Bang was very much a product of its time, so it's hard to imagine it taking place at any other time. As one of the last great sitcoms before the age of streaming, though, Big Bang's concept would've felt right at home in the '90s, alongside other sitcom titans like FriendsFrasierSeinfeld, and Will & Grace. This '90s version of The Big Bang Theory would've premiered in 1997, and the cast would've been a curious mix of '80s stars and '90s newcomers.

Patrick Dempsey As Leonard Hofstadter

patrick Dempsey in Can't Buy Me Love

During the 1980s, Patrick Dempsey rose to prominence thanks to teen films like Can't Buy Me Love and Some Girls. He then moved on to more mature leading men roles in rom-coms like Loverboy and Happy Together. However, his career slowed down in the early '90s after starring in several failed pilots.

In 1997, Dempsey would've been an excellent choice to play the shy but brilliant Leonard. Perhaps he is a tad too conventionally good-looking, though, but back in the '90s, that wasn't a problem. Dempsey was enough of a big name to carry the show, and his natural charisma fits the character like a glove.

Alan Ruck As Sheldon Cooper

John Harriman sitting on the Captain's chair of the USS Enterprise-B

Like Dempsey, Alan Ruck made a name for himself during the '80s. His most prominent role was Cameron Frye, Ferris Bueller's hypochondriac best friend in the now seminal classic Ferris Bueller's Day Off. He later appeared in 1987's Three for the Road and 1989's Three Fugitives. His career carried on during the '90s, and in 1994, he played Captain John Harriman in the Star Trek Generations film.

It's hard to imagine anyone other than Jim Parsons playing the role of Sheldon, but Ruck could've made it work. He is significantly older than Sheldon is supposed to be in season 1, but Ruck always looked younger than he was. In fact, Ruck was 30 when he played Cameron in Ferris Bueller, proving that age is just a number.

Rose McGowan As Penny

Tatum talking to Sydney

After receiving acclaim for her performance in the 1995 dark comedy, Doom Generation, Rose McGowan had her breakthrough role in 1996's ScreamThe movie was a huge success, redefining the slasher genre for a '90s audience and making stars out of its young and attractive cast. McGowan spent the latter part of the '90s making indie films, like Going all the Way, and cult classics, like Jawbreaker.

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McGowan would've been at the height of her post-Scream popularity in 1997, making her the ideal choice to portray the bubbly and outgoing Penny.

Andrew Cassese As Howard Wolowitz

Promotional photo of Andrew Cassese

Andre Cassese's most significant performance was in the 1984 cult classic Revenge of the Nerds. He reprised the role in the 1987 sequel, Revenge of the Nerds II: Nerds in Paradise. Unlike Dempsey and Ruck, Andrew Cassese's career didn't carry on to the '90s. The actor chose to instead focus on his education, graduating from NYU Film School in 1995.

Cassese would've fit in with the nostalgia of Dempsey and Ruck's characters, making him the right choice to portray the desperate and slightly creepy engineer, Howard Wolowitz.

Vivek Mushran As Rajesh Koothrappali

Vivek Mushran in a Bollywood movie

During the '90s, Vivek Mushran achieved great fame in Bollywood. He began his career with the 1991 blockbuster Saudagar before appearing in other films, like First Love Letter and Prem Deewane.

In 1997, Mushran would've been virtually unknown to Western audiences, but Big Bang would've been a great introduction. Casting a Bollywood star might've also stopped the show from making racist jokes at Raj's expense, which was always one of its worst offenses.

Ally Sheedy As Amy Farrah Fowler

Ally Sheedy next to a dog in Man's Best Friend

Another '80s star who would've perfectly fit this '90s version of Big Bang would've been Ally Sheedy. After co-starring with Matthew Broderick in the 1983 hit WarGames, Sheedy went on to play her best-known role in 1985, Allison Reynolds, "the Basket Case" in John Hughes' seminal film The Breakfast Club.

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One of the defining members of the Brat Pack, getting Sheedy would've been a big deal for the '90s Big Bang. Ruck, chosen to play Sheldon above, was never a part of the Brat Pack, but he did also make a name for himself by starring in a John Hughes film, so pairing him with Sheedy would've hit audiences right in the feels.

Courtney Thorne-Smith As Bernadette Rostenkowski-Wolowitz

Promotional photo of Alison Parker in Melrose Place

Most fans may know Courtney Thorne-Smith as Alan Harper's girlfriend, Lyndsey, in the last season of Two and a Half Men. Thorne-Smith played supporting roles in numerous '80s films before playing Allison Parker in five seasons of Melrose Place. 

By 1997, with her MP days behind her, Thorne-Smith would've been an inspired choice for the role of Bernadette. The character starts as a sweet and innocent young woman before turning into a fiercely competitive and domineering wife, and Thorne-Smith would've easily handled both sides.

Wil Wheaton As Stuart Bloom

Wil and Sheldon talk at the former's porch

In a whimsical piece of casting, and as a way of honoring the actual Big BangWil Wheaton might've been a great choice for Stuart. Wheaton, of course, began his career in the '80s, memorably playing Gordie in Stand by Me. From 1987 to 1994, he played Wesley Crusher in Star Trek: The Next Generation.

Wheaton's casting would've also helped Stuart's characterization. Fans remember that, when first introduced, Stuart is a successful and charming character that even manages to date Penny. His character goes horribly off the rails in later seasons, and Wheaton could've changed that.

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