'Big Bang Theory': Breaking Down Raj’s Romantic Twist and Why Leonard Did the Unthinkable (Exclusive)

It was a night of BIG changes on 'The Big Bang Theory’s penultimate episode!

It was a night of big changes on The Big Bang Theory’s penultimate episode!

The long-running CBS comedy is starting to tie up loose ends before we officially say goodbye to our geektastic gang with the series finale on Thursday, May 16.

This week’s heartfelt episode featured an emotionally-charged evolution between Leonard (Johnny Galecki) and his mother, Beverly, played by fan-favorite guest star Christine Baranski. Additionally, fans finally got an answer about Raj (Kunal Nayyar) and Anu’s will-the-won’t-they relationship.

Big Bang showrunner and executive producer Steve Holland is spilling exclusive details to ET about how these pivotal moments came to fruition in tonight’s episode entitled, "The Maternal Conclusion."

Longtime fans know that Leonard and his mom have not always had the most nurturing mother-son bond. As a neuroscientist as well as an award-winning psychiatrist and author, Beverly rarely offered warmth to her children – especially Leonard – so it’s was particularly baffling when Beverly spent the entire episode praising Leonard and his new job.

CBS

As it turns out, Beverly was only complimenting her son as part of a new paternal experiment she was conducting and although Leonard’s initial reaction was to scream at his mother for her lack of empathy, he also did the unthinkable: he forgave her.

Holland expressed that he and the Big Bang writers felt that it was very "important" to "put a pin in the relationship" between Leonard and Beverly by the end of the series.

"In these last few episodes, Leonard has gone through some character growth and it just felt like it was the right time for him to finally stand up to his mom," the showrunner revealed to ET over the phone earlier this week. “So we’d been talking about that scene and having [Christine Baranski] come back and having Leonard really put her in her place.”

"It was [creator and executive producer] Chuck [Lorre] who said, 'You know what? The best thing he can do is instead of yelling at her, is if he forgives her,'" Holland explained. "You expect him to sort of lay into her and chastise her for all the years she’s put him down – and instead, he forgives her. It just felt like a really powerful moment for this character."

CBS

Meanwhile, when Raj’s on-and-off-again girlfriend Anu revealed that she was going to take a full-time job in London, his love for over-the-top romantic gestures kicked into overdrive. He announced to his friends that he was going to fly to London and re-propose to Anu.

However, his big moment of romance turned into a full-on bromance when Howard chased Raj through the airport to stop him from getting on the plane.

"To us, that felt like a more satisfying end," Holland dished. "I think the Kooth and Anu storyline was really nice and good for Kooth and got him some growth, but it didn't feel right for us to have him go off and enter into this relationship."

"There’s always been a fun Howard and Koothrappali bromance at the center of this show and it felt like a really fun way to honor that and also like a way to keep things honest," Holland added.

The Big Bang Theory’s two-episode series finale airs Thursday, May 16 at 8 p.m. EST/PST on CBS.

Keep it locked to ETonline all next week for behind-the-scenes secrets about the final episode and exclusive peeks into the past with flashback interviews with the Big Bang cast!

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