The Maternal Capacitance Season 2, Episode 15 - Aired February 9, 2009
A visit from Leonard's mother, Dr. Beverly Hofstadter, brings misery for the gang, except for Sheldon who is enamored with Leonard's overly analytical mother. Leonard and Penny feel closer together with their shared discomfort around Leonard's mother, Howard and Raj are uneasy at Dr. Hofstadter's view of their friendship, while Sheldon and Beverly bond.
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Cast: Johnny Galecki as Leonard Hofstadter, Jim Parsons as Sheldon Cooper, Kaley Cuoco as Penny, Simon Helberg as Howard Wolowitz, Kunal Nayyar as Raj Koothrappali
Guest Stars: Christine Baranski as Beverly Hofstadter
Writers: Chuck Lorre (Story), Bill Prady (Story), Richard Rosenstock (Teleplay), Steven Molaro (Teleplay)
Director: Mark Cendrowski
Viewers: 12.7 million Households Rating: 7.8/11 Adults 18-49 Rating: 4.5/10
Episode Notes
- Episode Title:
- The
- Maternal 4
- Capacitance 1
- Due to a Presidental Address this episode originally aired at 21:30 following Two and a Half Men.
- The title references the built-up frustration evoked in Leonard by his mother's visit.
- This episode marks the first appearance of Christine Baranski as Dr. Beverly Hofstadter.
Official Podcast
#33. The Maternal Capacitance with Christine Baranski
October 27, 2025
Christine Baranski, who played Leonard's mother Beverly Hofstadter in 16 episodes of The Big Bang Theory, joins Jessica Radloff to discuss her first appearance in "The Maternal Capacitance". Baranski likens joining the series to "jumping onto a fast-moving train" and explains the intense obligation she felt to deliver. She shares whether she ever broke character while delivering Beverly's deadpan lines. Plus, she admits that singing "Any Way You Want It" with Jim Parsons at the end of the episode will make it onto her "lifetime highlight reel".
Episode Quotes
Beverly Hofstadter: It might explain why the two of you have created an ersatz homosexual marriage to satisfy your need for intimacy.
Howard: Say what?
Leonard: She's only been here a day and a half, and I'm seriously considering alcoholism as a new career path.
Penny: Hey, I talked to her for five minutes yesterday, and I've been half bombed ever since.
Beverly Hofstadter: If you want to have intercourse with that girl, find out what kind of cologne her father wore.
Penny: I'm curious. What was Leonard like when he was little?
Beverly Hofstadter: I think you mean young. He's always been little.
Penny: You can't let her get into your head.
Leonard: It's too late for me, my head is her summer house.
Recap
When Leonard's mother arrives at the apartment building for a visit, she meets Penny in the lobby. Dr. Hofstadter and Penny engage in small talk while climbing the stairs to Leonard's apartment, but by the time they get there Penny is in tears after a psychological grilling from Beverly. Leonard is unsurprised by the effect his mother had on Penny. Although Leonard is annoyed by his mother's nature, Sheldon is fascinated by her analytical mind.
When Leonard takes his mother to work, she manages to offend Howard and Raj by suggesting they're in an ersatz homosexual relationship. After trying and failing to get his mother interested in his work, Leonard goes to Penny's apartment to drown his sorrows with her. Meanwhile, Sheldon and Leonard's mother bond over their shared mental brilliance as they return from the hospital with a scan of Sheldon's brain.
While Leonard and Penny start kissing, Sheldon and Dr. Hofstadter have fun of their own with a karaoke game. After Leonard and Penny had progressed to the bedroom, Leonard says the wrong thing and causes Penny to throw him out.
The next day, as Beverly gets ready to leave, Leonard tries to apologize to Penny, who understands and tells him never to speak of it again. As she leaves the apartment, Dr. Hofstadter once again delves into Penny's mind and suggests she travel to New Jersey to have a brain scan.