Written by Phil Ford, of Coronation Street fame.
Rhys and Gwen finally get married. Oh, and on the morning of her wedding she's woken up heavily pregnant with an alien baby after being bitten by the father (a predatory alien whom Jack killed in a scuffle) the night before, 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, citing how expensive a wedding is, 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's best man, a twerp nicknamed "Banana Boat". Owen realizes that the alien baby is dangerous after all, in 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 reveals herself. She's a shapeshifter, and quickly disguises herself as Rhys's 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 and fall asleep.
Examples
- Artistic License – Religion: Jack references immaculate conception, which contrary to common misconception (no pun intended) is not about the virginal conception of Jesus by Mary but rather refers to the Catholic doctrine that Mary herself was conceived without the taint of Original Sin.
- Ask a Stupid Question...: Courtesy of Rhys when he and Gwen are on the run:Rhys: Are you alright?Gwen: I'm running around in a wedding dress with what feels like a keg of lager up my skirt. What do you think, Rhys?!
- Bond One-Liner: Jack after turning the Nostrovite mother into a shower of guts. "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.
Rhys: Fuck. - Double-Meaning Title: The title is a play on the "something borrowed" a bride is traditionally supposed to wear, as it takes place at a wedding, and the alien fetus Gwen has been implanted with has literally been "borrowed".
- Foreshadowing: Gwen proclaims that she will marry Rhys even if "the skies are full of spaceships" or "an army of Weevils climb out of the sewers in St Mary's Street".
- I'm a Humanitarian: Nostrovites eat people. Sometimes cocooning them to snack on later.
- More Teeth than the Osmond Family: Par for the course with Nostrovites, along with blood red eyes.
- Mister Seahorse: According to Jack, Nostrovites live in mated pairs; the male keeps the fertilised eggs in his throat and transfers them to a suitable host via a bite, after which the female tracks down and rips the young out of the host when it's time for them to hatch, keeping watch on the host in the meantime "like a midwife from Hell".
- Mistaken for Cheating: When Jack bursts into the chapel saying to hold off the wedding, several of the guests assume he's the baby's real father.
- Mistaken For Crossdresser: When Ianto is shopping for a maternity wedding dress for Gwen, the salesman assumes it's for him. "You'd be surprised. We're quite used to men buying for their 'friends'."
- Never Speak Ill of the Dead: Since Owen's new undead 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. - Picky Eater: Nostrovites apparently don't like carrion; the female ignores Owen when she realises he's technically dead.
- Shapeshifting: The Nostrovite's ability, which makes catching it a lot harder to do. Owen also comments, after determining the fetus is a Nostrovite, that when dealing with a shapeshifter it's difficult to know what kind it is.
- Shout-Out:
- Rhys, covered in blood and wielding a chainsaw?
Jack: The whole Evil Dead thing looks good on you, Rhys.- The episode was likely inspired by the Angel episode "Expecting", where Cordelia becomes fully pregnant overnight after being infested with the deadly spawn of a demon.
- Spotting the Thread: Tosh realizes something is afoot when "Cary" the Nostrovite leaves a black bloodstain on a tissue after being pricked by a flower pin.
