Thursday's episode of The Big Bang Theory, "The Fetal Kick Catalyst" introduced a new character: Mrs. Petrescu (Michelle Arthur), a woman who lives downstairs from Sheldon (Jim Parsons) and Amy (Mayim Bialik) — and by extension, Leonard (Johnny Galecki) and Penny (Kaley Cuoco). She only had a few lines, but she stole the episode.

Amy wants to start entertaining friends at her and Sheldon's new apartment, so Sheldon surprises her by organizing a brunch and invites Bert (Brian Posehn), Stuart (Kevin Sussman) and Mrs. Petrescu. (Leonard considers them all second-tier guests who are there for a trial-run brunch before he invites better friends.)

But Mrs. Petrescu is first-tier in my book, because she's TBS Very Funny.

Michelle Arthur, Mayim Bialik, Jim Parsons, Kevin Sussman and Brian Posehn, <em>The Big Bang Theory</em>Michelle Arthur, Mayim Bialik, Jim Parsons, Kevin Sussman and Brian Posehn, The Big Bang Theory

Mrs. Petrescu is from Romania, and her English isn't very good. She's learning the language from TV. Usually, watching TV is actually a pretty effective way to learn a language, but it's not really working for Mrs. Petrescu. It's not teaching her conversational English, just phrases devoid of context. She responds to things people say by associating them with words she's heard over and over on TV. She's like a parrot whose owner leaves CNN on all day.

Her first line comes when Sheldon hands her a mimosa, and she thanks him by saying:

Sheldon explains that she's learning English by watching TV, but the only word she catches is "TV."

Her best free-associative moment comes when she hears someone say "15 minutes" and she comes out with "15 minutes could save you 15% or more on car insurance."

Mrs. Petrescu has some stories to tell --like the one about how her sister's husband took everything from her — but we'll have to wait to hear it.

And she has good taste in sitcoms, so Cheers to her!

Here's hoping we see more of Mrs. Petrescu. It would be really fun to see her pop in a few times per season with a television-derived non sequitur.

The Big Bang Theory airs Thursdays at 8/7c on CBS.

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