The Big Bang Theory: The 10 Storylines The Cast And EPs Struggle With Now — Including Ill-Fated Penny/Raj Romance

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At 279 episodes, The Big Bang Theory holds the record for longest-running multi-camera comedy in television history. But not every one of those episodes has aged particularly well.

In the newly released oral history The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series by Jessica Radloff (order it here), cast members Jim Parsons, Kaley Cuoco, Mayim Bialik, Simon Helberg and Kunal Nayyar are among those who speak out about the storylines they struggled with at the time — and, in some cases, continue to struggle with now. And they're not alone: Executive producers Chuck Lorre, Lee Aronsohn, Steve Molaro and Steve Holland weigh in on a number of decisions they wish they could undo, from the Season 4 finale "sleepover" that sought to shake things up in a big way, to the surprise pregnancy that capped Leonard and Penny's 12-season journey.

Scroll down to review Big Bang's least flattering storylines, then hit the comments and tell us if you'd rewrite (or completely do away with) any of 'em.

In the series premiere, Leonard and Sheldon visit a high IQ sperm bank to, um... make deposits. Even weirder: It's Sheldon's idea to donate sperm in order to make a little extra money and put it toward faster internet. Lorre has since had the scene removed from syndication. "The scene was so wrong," he says in the book. "In my mind, the show truly began with those awkward hellos between Penny, Sheldon and Leonard when she's unpacking boxes in her apartment."

Parsons agrees with Lorre's assessment but defends the writing. "At the time, the sperm bank scene didn't bother me," the four-time Emmy winner says. "Looking back, it was out of place, but there was no way for the producers to know... Nobody knew who Sheldon was yet, so the live audience accepted it for what it was. But it is confusing information now, and I get why Chuck took it out of syndication, because the episode is much stronger and more special without it."

Lorre is the first to admit that the pilot didn't do right by Cuoco. "One of the most underwritten characters in the show early on was Penny," he says. "It was really obvious immediately that we hadn't developed that character beyond the pretty girl next door, and Kaley was certainly capable of doing a great deal more than what was asked of her."

Molaro also acknowledges the poor writing for Penny. "She was the ditzy blonde girl in the pilot, which is one of the things that is not great about [it]," he says. "There's an unfortunate joke about how she's a vegetarian but she loves steak. I didn't write the pilot, but those are moments [that] you wish you could undo a little bit of."

The Powers That Be make no excuses about Howard's behavior in the #BeforeBernadetteTimes. "What Wolowitz was... doing in the first season could be called harassment today," Aronsohn says. "I rewatched the pilot recently, and it did occur to me that the Wolowitz character was not 2021 friendly."

Even as the show was airing, portrayer Simon Helberg struggled to defend his character. "People were very unhappy with some of the things Howard would do or say, and I was like, 'Yeah, I agree,'" he says. "I didn't necessarily think that meant the character should be removed, but it certainly was more fun to play him as his heart got bigger and he shed his layer of sleaze.... The fact that you don't have to search too hard to find a handful of qualities and jokes from our show that didn't age well, to me is a good sign that we're growing up as a culture in some ways now."

It took until the Season 6 finale for Raj to overcome his inability to talk to women without alcohol — an anxiety disorder that grew tiresome for Kunal Nayyar. "It was definitely frustrating because there were episodes where I knew I could contribute in ways [but] I was handicapped by the character's issue," he says. "There were a lot of scenes where I would sit and sit and sit and then I would have to whisper something and Simon got to tell the joke. And then, after a while, I would open scripts and see if I was in scenes with a female character," at which point he knew he wouldn't have much to do. "After a while, the freedom to be able to speak without that was really nice, just from an acting point of view."

It was Lorre who proposed the controversial Season 4 cliffhanger — when Raj and Penny ended up in bed together — as a way to shake up the group dynamic. "I really did not like that season finale ending," Molaro admits. "I spent the entire hiatus being upset about it... I went upstairs to [Lorre's] office right when we got back to work [on Season 5] and said something like, 'This is really bothering me. I think I have a way that we can... get out of it and preserve the characters as they are.' He didn't love it, but he knew it was important to me to the point that he conceded." And it was Lorre, Molaro says, who came up with the "brilliant" idea that Raj suffered from premature ejaculation, so nothing actually happened between him and Penny.

During Season 7, struggling actress Penny reluctantly agreed to appear opposite Wil Wheaton in a sequel to the low-budget horror film Serial Apeist. Cuoco hated the storyline, but not because of the rather repulsive pun. "The worst experience was filming Serial Apeist and getting covered in f–king hair from head to toe," she says. "I was like, 'Really, you guys? This is what's happening?' And Chuck just thought it was so funny. He loved it. I never understood why."

But Lorre says he didn't love the Serial Apeist storyline either. "We wanted Penny to have some small success in her from of being a successful actor, but it's not my favorite episode," he explains. "Doing a show within a show — writing the 'bad' scenes that she's in in an otherwise good show — was not our finest moment. The goal was legitimate, which was to put her in a bad move and see her struggling to make something work."

Shortly thereafter, Penny quit acting and became a pharmaceutical sales rep.

Parsons felt strongly about Sheldon moving across the hall in Season 10 — not about moving in with Amy, but about his alter ego's willingness to swap apartments with Penny. "They made it work... but I mostly had to ignore my own feelings, which was, 'This is out of whack!'" Parsons recalls. "At the very least, I couldn't believe it wasn't a two-part very special episode where [Sheldon] ties himself to the kitchen island and won't leave! But that wasn't what they wanted to do.

"Looking back, I'm still not at peace with it, but when we did it, I basically just chose not to think about it," Parsons continues. "This is about making bold, creative choices that some people are going to be unhappy with. And I wasn't unhappy with the result. I loved living over there, actually! I thought Penny's apartment was cute."

After Penny made clear that she didn't want to start a family with Leonard (more on that in a bit), Leonard considered donating his sperm to Penny's ex-boyfriend Zack and his new wife Marissa — a scenario that didn't sit well with Penny or Cuoco. "Listen, there's a lot of storylines you need if you're going to run 12 years," she says. "You're going to hit a doozy once in a while!" As for why Leonard didn't go through it Holland says that "we talked about going down [that] route where Leonard was the sperm donor... but the conclusion we came to was that it wouldn't feel OK. People had different opinions about it in the writers room," but the general consensus was "that it wasn't going to be satisfying."

Dr. Fowler's extreme makeover — which came after the newly-minted Nobel Prize winner realized that her sudden fame came at a price (read: photos of her self-described "frumpy" appearance would spread online) — didn't sit particularly well with Mayim Bialik. "This is a case where I don't know that I agreed with our writers," she says. "I loved that I got to wear some nicer clothes, and it was really a thrill to have my hair cut after having the same [style] for all those years... but in some ways, it did feel like a betrayal of our Amy. We didn't go crazy and have her dressing in ways that completely didn't look like her... but it was definitely something I had conflict about. I thought it would be, 'Let's dress Amy up and take her out for the night!' I didn't think it would be, like, here's her new normal."

Early in Season 12, Penny firmly declared to Leonard that she did not want children. But in the series finale, Leonard and Penny were expecting — and Penny seemed quite happy about it. "I actually wished that they did not [make Penny pregnant], because I loved that message [of Penny not wanting kids] so much," Cuoco says in the book. "It was cute how the writers did it at the end with Penny's surprise pregnancy, and all in all I'm glad, but I was actually voting for her not to [get pregnant]."

Holland concedes that the pregnancy reveal didn't go over well because the series hadn't earned it. "We talked about whether there were other ways to do it, like what if she had a pregnancy scare that turned out to be false and she was disappointed. We talked about ways to get her to that moment that didn't feel quite so abrupt," he recalls. "I wish we had Penny take one more step before we got to the finale. The way the last episodes broke out, we just didn't get there. But with that said, I do think it was a great landing place for [Penny and Leonard]. We really wanted to honor that relationship, as well as the 'Our babies will be smart and beautiful' line from the pilot as a way to tie it back together."