A highly experimental episode, which offers the same story twice from two different perspectives — not unlike the earlier "Flip-Flop".It's one of the very few episodes in the Companion Chronicles series to feature the Doctor (Sixth in this case) played by his own actor, instead of being a story entirely narrated by his companions.
Peri and the Fifth Doctor land in Los Angeles in 2009. Peri is curious and a bit scared at seeing the future of her own country, and even moreso when she spots a much too skinny woman staring at her from across the street. While the Doctor goes off to investigate a matter concerning an ocean-stealing space fish named Zarl (a "piscon"), Peri secretly follows him and finds the Doctor, said giant fish, and her own future self.With the giant fish running off after a brief struggle with the Doctor, Peri's future self, a secret agent for the The X-Files, takes her to an Are You Being Served?-themed coffee place (complete with a giant grinning John Inman on the wall and some very bad puns on the level of "Grace And Flavor"). Older Peri is keen on telling her younger self all about her adventures as a hardboiled alien slayer. But young Peri is much more interested in the things that really matter to her: did she end up marrying her nice blond high school sweetheart? Did they have the three kids she always wanted? (And what's up with that obvious nose job?) Older Peri says that she did, and the kids all have dream jobs and dream lives. After making sure that her older self really does have the same memories she has, Peri is rudely interrupted by a different giant space fish, and the whole gang (including older Peri's hapless personal assistant, Beretta) have to flee.During a second confrontation with Zarl, older Peri finally reveals what's going on: the Piscon discovered that when they die, many of their souls reincarnate as humans on Earth. Beretta is actually the new form of Zarl's dead wife, and the reason she had a lot of plastic surgery is to subconsciously emulate the look of a fish. Zarl isn't here to steal ocean water — he's here to reunite with his lost love. And because the Piscon race can't kill themselves (to prevent mass suicide of space fish looking for lost loves on Earth), he wants the Doctor to do it for him. All the evil villainy thus far, as well as the rest of his helpful evil to-do list, was just to bait the Doctor into killing him.While Beretta tries to cope with that information, the Doctor captures Zarl with timelocked handcuffs, tells Peri the combination and simply phones the Piscon police. Young Peri stays with Zarl, and is surprised to hear the fish speak very gently of the woman he lost. But older Peri, remembering the lock combination from when she was young Peri, frees Zarl, who escapes in the confusion. The whole thing culminates in a fight at the docks, where older Peri shoots both Zarl and Beretta (who by now believes she's a Piscon queen) in cold blood. Young Peri is horrified, especially when she realises that all that talk about her kids was just a lie. She vows that she'll never become this woman. The Doctor tries to explain how people can change over time, but stops just short of revealing the idea of regeneration to her, deciding that it hopefully won't ever be necessary for her to know. They vworp off in the TARDIS, towards Androzani Minor.
Dr. Perpugilliam Brown, a world famous celebrity talk show host (with a doctorate in botany), is confronted by the Sixth Doctor while having coffee with her best friend Beretta (short for Carberetta — the woman had white trash parents) in her favourite Are You Being Served?-themed coffee place. The Doctor is shocked to hear that Peri doesn't recognise him. He can't tell her about what's supposed to have happened to her, but he sets about sorting the whole thing out. Peri, for her part, just doesn't believe that he's the same guy as that dishy blond floppy-haired P. G. Wodehouse style Doctor she once had a brief adventure with.The Sixth Doctor explains that he's having some memory troubles concerning this day, and he can't quite put his finger on it, but the apparent Peri paradox had to do with the death of a space fish named Zarl. Since the whole thing ended at the docks, the two vworp over there, where they immediately spot Zarl, startle him by yelling his name, and cause him to fall over and die.The Doctor is pretty sure that was really not supposed to happen, so he decides to redo the rest of the adventure dressed up in a giant space fish suit, in order to preserve the Web of Time. He rigs a fake gun to teleport him back to the TARDIS instead of killing him when it's fired, and hopes he can convince Five to shoot him. He and Peri load Zarl's corpse into the back of her car and go off to antagonise Five.Five being Five, of course, he doesn't kill "Zarl" at all, but instead tries to be nice to him. "Zarl" runs off, and older Peri takes younger Peri to the coffee place, pretending that her life is all sunshine and roses and secret agent hijinx (and sidestepping the question of the nose job). Five sees right through older Peri's X-Files fib (commenting that her organisation became a bit rubbish after David Duchovny left) but commends her on preserving the Web of Time by lying to her younger self.However, the dead space fish in her trunk attracts unwanted attention from the Piscon police, and since Six really doesn't want to be jailed by Piscon cops, he and older Peri invent a new story about reincarnation and a lost love. Beretta is roped in to play along. Five still doesn't see all that as a reason to commit murder, though, and after he's handcuffed, Six simply tells Peri the lock combination and swans off down the fire escape. After the confrontation at the docks — and finding herself forced to murder Beretta — older Peri quietly breaks down, realising that she'll never be able to tell younger Peri what her life is really like. Her dashing blond high school boyfriend, the one she was so keen on, ended up abusing her, destroying her ability to have children and shattering her nose. But she'll never be able to reveal it to her younger self, and now younger Peri will have to find out on her own that cute, floppy-haired blond men can very quickly turn into violent jerks.She and Six get rather rudely interrupted by a Time Lord in L.A. beach gear, representing the Celestian Intervention Agency. Said Time Lord finally explains how older Peri can be here: after Peri was killed during the Sixth Doctor's trial, the Time Lords took mercy on her, crafted a new timeline and granted another version of her life as King Yrcanos' bride. Realising that such a thing could actually be worse than death, they then crafted a few more timelines just for the hell of it, including this one... with her memories of the Doctor removed apart from their first adventure, just like they did with Jamie and Zoe.Peri is a bit disturbed to hear that there are four more versions of her out there... until the Time Lord tells her that the Peri living with King Yrcanos has three beautiful children. And since that's the one thing she wanted most, she accepts it and goes back to her daily life.