Rhys and Gwen finally get married. Oh, and on the morning of her wedding she's woken up heavily pregnant with an alien baby, and the mother wants it back.Jack tells Gwen to cancel the wedding and go to the Hub. She goes into Bride Zilla mode and adamantly refuses, instead choosing to tell her parents and guests that she's just been hiding her pregnancy with special clothing. Since Owen's quick tests didn't reveal any kind of dangerous alien they already knew of, Jack decides to just let her go ahead.Tosh stays with Gwen and tries to shake off the advances of Rhys' best man, a twerp called "Banana". Owen realizes that the alien baby is dangerous after all and that it's going to be ripped out of Gwen any moment by its mother. But before they can get Tosh to tell Gwen about it, the alien mother captures Tosh and Banana and traps them in its sticky goo.Just when the guests are being asked if anyone objects to the wedding, Jack bursts in and the alien mother eveals herself. She's a shape-shifter, and quickly disguises herself as Rhys' mum to escape.Gwen hides herself in her room. Jack comes to visit her, and for some reason, Gwen decides to try and kiss him. It's not Jack, though — it's the alien again. Gwen is appropriately embarrassed as she escapes.Eventually, Owen decides to just destroy the alien with his Martha-saving gadget. But since he broke one of his fingers and then cut his palm in an act of defiance last episode, he can't work the gadget, and Rhys has to do it. He does, saves Gwen's life, charges at the alien mom with a chainsaw and almost gets killed until Jack saves his life with a BFG.Owen has absolutely stopped giving a fuck about Tosh's feelings for him, so he dances with her and doesn't care one way or another about whether or not it's a date. Jack dances with Gwen until Ianto cuts in. Also, all of the guests are liberally drugged with Retcon.
- Bond One-Liner: "How's that for a shapeshift?"
- Bride Zilla: Gwen turns into this due to the stress.
- Chainsaw Good: Rhys grabbing a chainsaw and brandishing it in front of the Nostrovite, telling it to back off of his wife...
- Oh, Crap: ...only for the motor to fail as he finishes his speech.
- Mistaken For Crossdresser: When Ianto is shopping for a maternity wedding dress for Gwen, the salesman assumes it's for him.
- Never Speak Ill of the Dead: Since's Owen's new status, there has been a change in his relationship with Ianto.Jack: What is with you, Ianto? Ever since Owen died all you've done is agree with him!
Ianto: My mother taught me never to speak ill of the dead, even if they do most of the talking for themselves.
- Shapeshifting: The Nostrovite's ability, which made catching it a lot harder to do.
- Shout-Out: Rhys, covered in blood and wielding a chainsaw?Jack: The whole Evil Dead thing looks good on you, Rhys.