"Mac Bangs Dennis' Mom" is the fourth episode of the second season of It's Always Sunny in Philadelphia.

A visit to Frank's ex-wife's house turns into a web of back-stabbing and deception after Mac has sex with Dennis' mother and Charlie hatches a plan to get close to The Waitress.


4:30 PM on a Friday

Mac is sent by Frank to pick up his toupee from his ex-wife's house. When Barbara finds out that Frank is dating again, she attempts to seduce Mac.

Back at Paddy's, Dennis attempts to blackmail Charlie into getting out of Charlie Work by threatening to sleep with the Waitress. As he leaves, Mac enters Paddy's office to ask Charlie if it is wrong or right to sleep with Mrs. Reynolds. Charlie, with a newfound hatred for Dennis, says he should bang her. As he leaves, Dee enters and demands her old job back. Charlie offers her job back if she helps him derail Dennis. Charlie calls Dennis to prevent him from banging the Waitress.

After sleeping with Barbara Reynolds, Mac leaves the Reynolds house. Charlie and Dennis watch Mac leave from the Range Rover. Charlie convinces the only way to pay him back is to sleep with Mac's mother. Dennis attempts to seduce Mrs. Mac but she tells him that she doesn't find him sexually attractive, which shatters him. Dee and the Waitress watch him attempt to bang her, which in turn shatters the Waitress.

The next day, Dee enters Dennis' apartment and tells him that Charlie is refusing to give them their jobs back and that Dennis should bang Charlie's mother to get back at him. The Waitress watches as Dennis attempts to seduce Bonnie Kelly - who turns down Dennis as well. Dee tells the Waitress that she needs to sleep with Charlie to pay Dennis back.

Frank goes on a date with a friend from high school and realizes he is only attracted to younger women. He takes Mac out to be his wingman where Mac learns that Barbara is attracted to money. He brings a wad of cash back to her house to woo her, but she reveals she only slept with him to anger Frank. She slams the door in Mac's face, and Dennis approaches. He attempts to work out his anger via discussion, but the two men end up fist fighting.

Back at Paddy's, Dee helps Charlie prepare for his date with the Waitress. A disheveled Waitress enters with Frank and reveals that she slept with him to get back at Dennis. Dennis, who isn't attracted to her, doesn't care. Charlie, on the other hand, is shattered and wells up.




Guest StarringEdit


  • The vocals for the club music that Frank dances to were actually done by Rob McElhenney and Glenn Howerton. The song itself was influenced by an ad-lib did when Danny DeVito started dancing and singing 'go for it'.
  • The audio commentary for this episode captures the exact moment when Rob McElhenney, Glenn Howerton, and Charlie Day had the idea to have Frank carry a gun at all times. Charlie Day jokes: "Danny, you should constantly be dancing on our show. Dancing, and carrying guns," To which Glenn Howerton responds, soberly: "Now there's an idea. Let's have him carry a gun all the time."
  • Dennis actually had the last laugh in the episode for both Charlie and the The waitress.
    • While Dennis failed to bang both Mac and Charlie's moms as revenge for Mac banging his, and exposed him to the waitress, he still succeeded in getting out of Charlie work.
    • The waitress (who is at an even lower standard than Charlie) deliberately had sex with Frank to get back at Dennis for betraying her by seemingly having sex with Mac and Charlie's moms, but it was completely all for naught and pointless since Dennis never gave a crap about her to begin with, and only used her for his own means, nothing more. To add insult to injury, Dennis never even slept with both old women, thus Reynolds had the last laugh in the end.
  • When Frank is demonstrating his dance moves to Mac at the club, a waitress is seen passing behind him. It cuts to Mac's reaction for a second, then when it cuts back to Frank the same waitress passes by in the same direction again.
  • The waitress Frank looks up-and-down is Danny DeVito's daughter, Lucy DeVito. She appears in several episodes of Sunny in a variety of small roles.
  • Tchaikovsky's "Dance of the Fairy Dragee" (from The Nutcracker ballet) starts playing on 10:29.
  • The exterior used on the show for Mrs. Mac's house is actually next door to creator Rob McElhenney's childhood home in Philadelphia.
  • Frank finally finds out that Mac banged Barbara during the episode "The Gang Gives Frank an Intervention".
  • At 20:02, right after Barbara slams the door in front of Mac, you can see the door curtain falling off, and Mac's reaction - his head looking down to it and him saying "Oh!", yet right after it cuts back to Dennis' car you can see the curtain is back on.


Mac: That was, like, the best sex I've ever had, Mrs. Reynolds. Like something magical happened.
Barbara Reynolds: Hmm?
Mac: I was just saying that that was, like, so special, and, I mean, it was like magic...
Barbara Reynolds: You aren't going to start talking about your feelings and shit, are you?

Dennis: (after witnessing his Mom kiss Mac at her front door) Oh my God! Ohhh...
Charlie: Yeah... that's a terrible thing... a terrible thing for you to see that.
Dennis: I'm gonna kill him. I'm gonna kill him!
Charlie: Wait wait wait! What are you gonna do? Punch him in the face? Throw him? Maybe work the body a little?
Dennis: I was gonna...
Charlie: No no no, that's not gonna help. That's not gonna help and I'll tell you why: It doesn't unbang your Mom.

Dennis: (to Mac's mom, who he is trying to bang) Don't fight it, Mrs. Mac. Why don't we go inside and have a little fun?
Mrs. Mac: Don't find you attractive.
Dennis: What?
Mrs. Mac: I think you're an ugly man.
Dennis: You think I'm ugly?
Mrs. Mac: Yeah.
Dennis: I'm not ugly. You're ugly.
Mrs. Mac: Yeah.

The Waitress:"I'm going to stab him, I'm going to stab his face off!"

Dennis: What the hell is she doing here?
The Waitress 'What the hell is she doing here?' Really? Really? I'll tell you what I'm doing here. You wanna know what I'm doing here, shit for brains? I had sex with your dad. That's right! I had sex with your father because just like you, I like my sex old and ugly. And with fake hair on their heads so that it falls off when you're having sex with them, it just falls off! Because that's what you do, Dennis Reynolds. You like to have sex with old people. And you said that you loved me. You said, 'I love you.' And so I thought, 'Okay, well I love you too.' How do you show love? You go and have sex with old people, So that's what I did too!

Season 2 Episodes
  1. "Charlie Gets Crippled"
2. "The Gang Goes Jihad"
3. "Dennis and Dee Go on Welfare"
4. "Mac Bangs Dennis' Mom"
5. "Hundred Dollar Baby"
6. "The Gang Gives Back"
7. "The Gang Exploits A Miracle"
8. "The Gang Runs for Office"
 9. "Charlie Goes America All Over Everybody's Ass"
10. "Dennis and Dee Get a New Dad"