1. Penny and Leonard Make It Official

Showrunner Steve Molaro joins for a deep dive into the highly anticipated Penny and Leonard romance that launched Season 3 of "Big Bang."

2. The Evolution of Howard Wolowitz

The one and only Simon Helberg joins host Jessica Radloff for a nostalgic look back at his 12 seasons as fan favorite Howard Wolowitz.

3. Sheldon vs. Wil Wheaton

Sheldon Cooper's ultimate nemesis, Wil Wheaton, joins host Jessica Radloff to look back on his unforgettable run on "The Big Bang Theory."

4. The Bernadette Effect

The hilarious Melissa Rauch joins Jessica Radloff to discuss how she landed the role of Dr. Bernadette Rostenkowski-Wolowitz on "The Big Bang Theory."

5. Of All 279 Episodes, This One Is Kunal Nayyar's Favorite

Kunal Nayyar joins host Jessica Radloff to revisit his all-time favorite episode of "The Big Bang Theory": "The Adhesive Duck Deficiency."

6. How the First Female Writer Changed 'The Big Bang Theory'

When Maria Ferrari joined "The Big Bang Theory" in S3, she became the show's first female writer — and helped bring a fresh perspective to the series.

7. When Penny & Leonard (and Kaley & Johnny) Broke Up

Director Anthony Rich shares what was going on behind the scenes during the storyline of Penny and Leonard's breakup in Season 3.

8. Mayim Bialik & the Women Who Changed 'The Big Bang Theory'

Mayim Bialik and "Big Bang" writer Maria Ferrari join Jessica Radloff to discuss how Amy Farrah Fowler and Bernadette changed the series forever.

9. The Origin of Apartment 4A

From the group's first meeting to the story behind the broken elevator — director Mark Cendrowski talks about the infamous flashback episode.

10. How Stuart Got His Own Spin-Off

Kevin Sussman joins host Jessica Radloff to share what went through his mind when he learned Stuart Bloom would be getting a "Big Bang" spin-off.