Mayim Bialik's series Call Me Kat is set for another Big Bang Theory alumnus on its roster. Maria Ferrari has been added as new showrunner, along with Jim Patterson. Mayim Bialik is open about her love of sci-fi and comic books, and as The Big Bang Theory grew in popularity, it embraced plenty of opportunities to celebrate major sci-fi franchises.

Many episodes were rife with Star Wars references, and the show was instrumental in celebrating and normalizing geek culture. And no matter who they eventually married, it's comforting to know that Leonard, Sheldon, Raj, and Howard never really forgot their truest love: George Lucas.

The Force Awakens Arrives

Season 9 of The Big Bang Theory when the guys go to see Star Wars

"The Opening Night Excitation" is keyed to the much-anticipated premiere of the sequel trilogy, The Force Awakens. Like all good super-fans, the guys plan for a midnight showing to watch their Star Wars heroes. But it's also Amy's birthday, and she's not happy with the Sheldon-centric day her boyfriend has planned.  Sheldon gathers some advice from Professor Proton, who shows up as a Force ghost.

While The Big Bang Theory die-hards regard this as a landmark episode for the moment Sheldon and Amy have sex for the first time, it's, more importantly, a moment of personal growth for him in addition to operating as a bittersweet reminder of early fan excitement for TFA. Sheldon's willingness to forfeit his original plans to see the first Star Wars movie in several years was a sacrifice that Season 1 Sheldon would never have made.

James Earl Jones Is Delightful And Sheldon Can't Hang

James Earl Jones and Sheldon at a karaoke in The Big Bang Theory

"The Convention Conundrum" sees the guys panicking when they fail to secure tickets for Comic-Con. Sheldon decides to host his own convention instead, and invites the epic voice of Darth Vader, James Earl Jones.  He was thrilled with Sheldon's company, and they share a breakneck evening. Sheldon tries, but Jones is just getting started for the evening. He then plays a practical joke on Carrie Fisher.

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Given Sheldon's long string of restraining orders from various members of the scientific and sci-fi community, viewers cringingly watched him approach Jones after tracking him down in a restaurant. The turnabout of seeing Sheldon tire in the ebullient company of one of his heroes showed a new side of his personality -- it turns out that Sheldon can weary of his obsessions. Sheldon acts as though he only focuses on reality, but when he can't hang with what that reality is, he nopes out.

Leonard Fakes A Journal Entry

Penny and Leonard sitting next to each other in The Big Bang Theory

"The Platonic Permutation" is usually remembered for the revelation that Leonard read Penny's diary, generally thought of as one of the worst things he ever did on TBBT. To placate Penny, he offers to read her a few lines from his own journal. "Penny's beauty, like our love ..." he begins. But his wife isn't having it, and snatches his iPad to reveal the real entry: "OMG, OMG, we're so close to the new Star Wars!"

While the TFA reference is a neat nod to the wild anticipations fans built for the sequel trilogy, the best aspects of this episode explored how both halves of the couple dealt with Leonard's betrayal of Penny's trust. Even more importantly, it delves into Leonard's function as the constant pursuer in the relationship, and the ways in which Penny coasts. Even so, that's not permission for the self-proclaimed "king of husbands" to read his wife's diary -- accidentally or not.

Sheldon & Leonard Crash Skywalker Ranch

Leonard and Sheldon arrive at Skywalker Ranch in The Big Bang Theory

The dream of pretty much every Star Wars fan, outside of appearing in a canon production, is to undertake a tour of Lucasfilm's Skywalker Ranch. Leonard intends a mere drive-by, but Sheldon, as always, has other ideas. He tries to make a run for it into the compound, and both guys end up in a security office with a fellow fan.

"The Skywalker Incursion" held up a mirror to the roommates' extreme fandom. They soon discover that they're not the least well-adjusted people in the room, and while Leonard seems disturbed, Sheldon is upset only that they weren't able to sneak in where their fellow prisoner has. It's yet another example of Sheldon's obliviousness, but for Leonard, now engaged to Penny, the debacle is perhaps a sign that it's time to grow past such shenanigans.

Professor Proton Shows Up On Dagobah

Sheldon and Professor Proton talking in a dream in The Big Bang Theory

The legendary Bob Newhart served as Professor Proton, who becomes Sheldon's spirit guide in "The Planetarium Collison." He appears in a dream to dispense some marriage advice.

RELATED: Every Professor Proton Episode Ranked

Sheldon and Arthur are on Dagobah, where Luke Skywalker undertook most of his training. It's a signal of Sheldon's need for guidance; with his father gone, he needs the guidance of an older man who he admires. The episode contains several threads of the main characters grappling with marriage and career-related issues, indicating how much the gang has grown since viewers first met them.

Sheldon Expresses Every Star Wars Fan's Relationship With George Lucas In a Single Line

Sheldon in his desk, looking confused in The Big Bang Theory

In "The Lizard-Spock Expansion," Leonard suggests watching the animated series Clone Wars. Sheldon, however, firmly refuses, as he has not yet seen the movie that operates as its pilot. "I prefer," he explained, "to let George Lucas disappoint me in the order he intended."

This priceless observation perfectly encapsulates the complex relationship nearly every fan has with Star Wars creator George Lucas. It underscores the tendency of Star Wars fans to build up enormous expectations for new adventures, then loudly declare their disappointment. They no longer trust Lucas, and many don't trust current owner Disney, either, but they keep lining up for the next film.

"It's A Trap! It's A Trap!"

Sheldon outside his apartment in The Big Bang Theory.

"The Dead Hooker Juxtaposition" reflects a line from Return of the Jedi that became a widespread pop culture meme, and showcased Sheldon undertaking multiple attempts to perfectly mimic Admiral Ackbar's famous line. The performance does nothing but confuse Penny, however, who later finds herself entangled in one of Sheldon's beloved guessing games. "Are you Star Wars?" she finally asks in exasperation.

RELATED: 10 Things Only Diehard Star Wars Fans Know About Admiral Ackbar

That showrunners would include a moment from Star Wars fan life that extends beyond the movies themselves is an indicator of how effectively the fanbase was communicating with one another at this point. It's also a sign of how TBBT helped to popularize and normalize geek fandom. Best of all, the episode provides another window into the Sheldon-Penny sibling relationship.

The C-3P0 Shoutout

Star Wars The Rise of Skywalker C-3PO

"The Vegas Renormalization" took place early in the run of The Big Bang Theory. Leslie Winkle, although she and Leonard never got together on TBBT, decides to end a fling with Howard. Raj and Howard point out Sheldon's multiple comparison points to everyone's favorite protocol droid.

Sheldon's initial surprise at the Threepio comparison shows his lack of self-awareness and inability to understand sarcasm. He's more flummoxed than offended, and, one suspects, somewhat honored. Early Sheldon sought to avoid human contact as much as possible, and what better way than as a non-human?

Coldness Is Hothness

Leonard, Howard, and Sheldon in The Big Bang Theory. They are shown wearing orange hooded coats and standing in the freezer

When the guys go to the North Pole to conduct some experiments in "The Monopolar Expedition," Howard calls to mind the scene in The Empire Strikes Back in which Han Solo cuts apart a Tauntaun and stuffs Luke Skywalker inside to save his life.

Wherever more than two Star Wars fanatics are joined together in a cold place, references to the frozen planet of Hoth must result. That the showrunners recognized this was a tribute to their understanding of the fanbase, and the immediacy with which the guys reached their limit with Sheldon underscored his ability to wear the patience of even his closest friends.

Star Wars Day!

The Proton Transmogrification

The entire episode is given over to "Star Wars Day," May 4th. With nearly too many Star Wars references to count, including a Death Star cake that rolls off Bernadette's dining room table, "The Proton Transmogrification" was the first episode to showcase Bob Newhart as a Force ghost.

Sheldon schedules a Star Wars viewing marathon, including The Phantom Menace, after which he blocks in an hour for complaining -- and he's concerned that's not enough time. While Sheldon is known for his super fandom, his calm expectation of whining in TPM's aftermath is an affectionate nod to the inability of many Star Wars fans to reconcile themselves to the reality of Jar-Jar.

NEXT: The Biggest Changes in Sheldon From Season 1 To Season 12