Mammy Swings! is the sixth episode of the third series of Mrs Brown's Boys and is the season finale.
Mark finishes work on Agnes' new kitchen, and Rory announces that celebrity wedding organiser LaLa Doggie will be organising his and Dino's wedding. Agnes invites Mick's parents to the wedding, then invites them to her place so she can meet them, but Mick is worried about it and tries to warn Agnes that they are swingers. Mr and Mrs O'Leary are always laughing hysterically for no apparent reason, and Mr O'Leary claims he has a huge penis. Agnes also gets a shock when she returns to the sitting room to find them completely naked.
Agnes then holds a family meeting in the sitting room where LaLa and Maria pitch ideas for Rory and Dino's wedding. While LaLa proposes an underwater wedding so the event will stand out, Maria has gone more along traditional lines with the two grooms walking down the aisle in white suits to the song Nights in White Satin. When neither Rory or Dino can decide, Grandad manages to ruin the mood by saying Strictly Come Dancing is on. Rory bursts into tears and runs off with Dino going after him.
The next day, Dermot tells Agnes that Rory and Dino have gotten married in a private ceremony. A big party is planned for the newlyweds return, but Rory and Dino make an unceremonious entrance when their car comes crashing through the kitchen wall. When Rory asks his mother to say something, Agnes simply says she didn't like the new kitchen anyway.
The episode and the season ends with the cast performing Greased Lightning.
- The character LaLa Doggie is most likely a parody of Gok Wan.
- Agnes: (to LaLa Doggy) Listen you, you're not Gok Wan! You're not even Gok Two!
- Agnes: (about Mick's parents) What a pair of fruitcakes!
- Agnes: I'm sure that willy winked at me!