Big Bang Theory: The Awkward Way Johnny Galecki Asked Judd Hirsch To Be His Dad

"The Big Bang Theory" definitely welcomed more than its fair share of absolutely wild guest stars throughout the years. Mark Hamill. Stephen Hawking. Carrie Fisher. Steve Wozniak. Stan Lee, Bill Gates, Bill Nye... the list goes on and on. Also, Wil Wheaton shows up sometimes.

"TBBT" was basically the biggest thing on television for years, so one would think it would be pretty easy to get actors to agree to appear on the show. As Johnny Galecki — who played Leonard Hofstadter for the entire series — showed, though, there's a wrong way to ask a fellow actor to appear on your show.

While the entire cast spoke to Stephen Colbert, the late night host asked which guest star was their favorite. Galecki replied, "Judd Hirsch was a big deal for me. We ran into him at some function and I ran up to him and I said, 'I'm just a massive fan of 'Taxi' and your role on that, and I kind of tried to base the purpose of my character on the purpose of your character.' And then I said, 'you wanna play my dad? You wanna come on and play my dad?' And I realized he might not have any idea what show I'm talking about, or that I'm an actor, even."

It's a great and very embarrassing story, but luckily, Hirsch did end up appearing on "TBBT" as Leonard's dad. But what did Hirsch think of this interaction from his point of view?

Hirsch, naturally, has his own side of the story... and it probably won't shock you to hear that Galecki's approach was even more awkward than he initially made it sound. Hirsch's telling of it is actually much funnier, because it comes with the revelation that, under duress, Galecki can't make eye contact with people.

"He just sort of cornered me one day," Hirsch said during an interview with TVGuide alongside Jermaine Fowler and Katey Sagal. "We were at a celebration of [television director] Jimmy Burrows' 1000th show, and at that celebration — since he did all the pilots of all the shows that we know, he did 'The Big Bang Theory,' believe it or not — and Johnny Galecki just came over to me on the stage when it was all over and he goes... and he doesn't like me to say this, but I'm gonna say it anyway, he always looks at the floor when he talks to you."

Hirsch continued: "'Would you like to be my father?' I go, 'Why not? Why not?" And Johnny said, "I never had a father on the show and I always thought that I was like you.' And I'm thinking, 'Where?' He actually thought that, in real life, that he could come from someone like me."

In the end, Hirsch was the perfect choice to play Dr. Alfred Hofstadter, an anthropologist who has long been separated from Leonard's mother Dr. Beverly Hofstadter (Christine Baranski). Beverly is introduced much earlier in the series, but Alfred doesn't show up until Season 9's finale, "The Convergence Convergence," followed by the Season 10 premiere "The Conjugal Conjecture." In these two episodes, after eloping in a disastrous chapel wedding in Las Vegas, Leonard and Penny (Kaley Cuoco) want to have another wedding with their friends and family actually present, which puts Beverly and Alfred into the same room at the same time. (This goes just about as well as you'd expect.) Alfred, though, makes an unexpected ally, forming a bizarre bond with Sheldon Cooper's (Jim Parsons) mother Mary (Laurie Metcalf), mostly because they both really hate Beverly.

Alfred and Leonard definitely have a somewhat rocky relationship, but the sweetest aspect of Alfred joining the fray is how fond he is of Penny. He also does truly love Leonard, even saying at the wedding that his time with Beverly was worth it because they both got Leonard out of their marriage. Hirsch's emotional side really comes through in this part, so it's a good thing Galecki accosted him at that event.

"The Big Bang Theory" is streaming on Max now.