Thursday's episode of The Office, "The Lover," showed us a sign of Pamela Morgan Beesly we had never seen before. Funny what Michael Scott doing your mom will result in.

That's right, after hitting it off in Niagara Falls, Michael and Pam's mom Helene are dating, and when Pam learns about this, she is absolutely livid. Even Jim is at a total loss.

By and large, the episode revolved around Pam and Michael fighting about this singular issue, but it sure was entertaining. The subplot of the night was Dwight spying on Jim.

Jealous of Jim's promotion, Dwight planted a listening device inside a wooden duck mallard he presented Jim as a gift. His efforts quickly and hilariously unraveled, obviously.

Pam's first and last smile of the episode came in the first five seconds.

As always, The Office quotes from the episode produced numerous memorable lines that ranged from subtle to passive-aggressive to hysterical. Some of our favorites:

Pam: I'm not apologizing to anyone. Michael owes ME an apology.
Michael: For trying to find happiness in the arms of a lover?
Pam: Don't call my mother your lover!
Kevin: Yes! That's what I'm talking about.
Andy: That is not okay dude.
Michael: Okay, in my defense...
Phyllis: Disgusting.
Creed: That's messed up man. | permalink

Michael: I assumed that you want me to be happy, because I want you to be happy.
Pam: Michael. Let me make this very easy for you. I COULD GIVE A SH!T ABOUT YOUR HAPPINESS. STOP DATING MY MOTHER!
Michael: You know what, I'm gonna start dating her even harder.
Pam: What's that supposed to mean.
Michael: You know what it means. | permalink

Jim: Oh, so Dwight gave me this wooden mallard as a gift. I found a recording device in it. Yes. So. I think if I play it just right, I can get Dwight to live out the plot of National Treasure.
Pam: You need to be more upset about this. She's your mother too now. Your mother is sleeping with Michael Scott. | permalink

Dwight: [to Michael] You know, I really would've appreciated a heads up that you were into dating mothers. I would've introduced you to mine. | permalink

Michael: [to Pam] You're just as stubborn as your mom - when you don't want to do something, you just don't do it. | permalink

Dwight: Volunteerism is important. Every weekend I volunteer at the local animal shelter, they need a lot of help down there. Last Sunday I had to put down 150 pets by myself. | permalink

Michael: I don't need to be friends with Pam. I have plenty of female friends. My mom. Pam's mom. My aunt... although she just blocked me on IM. What's her face, from Quizno's? I see her like four times a week. | permalink

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.