Peri and the Piscon Paradox (audio story)

Synopsis
The Doctor and Peri journey to Los Angeles 2009 to do battle with a Piscon. His name is Zarl, and he's a fish of utmost evil.

Zarl is going to steal all the water of Earth and sell it to the highest bidder. Or blow up the San Andreas fault. Or the planet. Or something like that. He's a bit vague on that point.

Fortunately, to stop him there’s help from an unexpected source: a future version of Peri. She knows Zarl's dark secret.

But should the future Peri be on Earth at all? Something smells fishy – and it's not just Zarl.

Cast

 * Peri Brown - Nicola Bryant
 * Sixth Doctor - Colin Baker

Continuity

 * The Fifth Doctor refers to the Pescatons, whom he claims are more violent than the Piscons. (AG: Doctor Who and the Pescatons)
 * The younger Peri wonders if her mother is still alive in 2009. (BFA: The Reaping)
 * The Fifth and Sixth Doctors also met each other in BFA: The Sirens of Time and BFA: The Four Doctors.
 * The older Peri claims that the disappearance of the Mary Celeste's crew was caused by Piscons wanting to take over human forms. This was later revealed to be completely made up. In reality, the First Doctor and his companions Ian Chesterton, Barbara Wright and Vicki Pallister were indirectly responsible for the disappearance as the TARDIS materialised on the ship shortly after the Daleks had arrived via their own time machine. The crew of the Mary Celeste mistook the cyborgs for the "Barbary Terror" and they jumped overboard. The Doctor and his companions were unaware of the name of the ship that they had landed on. (DW: The Chase) However, the Doctor later discovered his own involvement with the crew's disappearance as, earlier in his personal timeline, the Fifth Doctor told Alan Fitzgerald, a student summer intern at the Gogglebox, that he was "sort of" responsible. (BFA: The Gathering)
 * The Fifth Doctor tells the younger Peri that he understands exactly what she means when she says that she does not like her future self. The First Doctor was singularly unimpressed by both his second and third incarnations, whom he described as "a clown" and "a dandy" respectively whereas the Second Doctor shared his immediate predecessor's low opinion of his immediate successor. (DW: The Three Doctors, DW: The Five Doctors) The Fifth Doctor was repulsed by the manipulative nature of his seventh incarnation (MA: Cold Fusion) and was unimpressed by his tenth incarnation, though he was originally unaware of his identity. He mistakenly believed that he was a member of LINDA. (DW: Time Crash) Furthermore, in BFA: The 100 Days of the Doctor, the Sixth Doctor claims that, from what he has heard, his immediate successor is "always blowing up planets." (DW: Remembrance of the Daleks, NA: The Pit, NA: Blood Heat, MA: Cold Fusion)
 * In an attempt to jog the older Peri's memories, the Sixth Doctor mentions Sil (DW: Vengeance on Varos, BFA: Mission to Magnus, DW: Mindwarp), the Tractators (BFA: The Hollows of Time), the Ice Warriors (BFA: Mission to Magnus) and Davros (DW: Revelation of the Daleks).
 * The Sixth Doctor claims that he has been having difficulty with his memory since his most recent regeneration. This could account for the fact that he did not remember meeting Kathy Chambers for the first time in his personal timeline in Brisbane, Australia in September 2006 while in his fifth incarnation (BFA: The Gathering) when they met for the second time (from his perspective) in Baltimore, Maryland in September 1984 while in his sixth incarnation. (BFA: The Reaping)
 * The older Peri remembers her first encounter with the Doctor involving a "robot with an identity crisis", "some religious types" and a "crazy guy with a beard". (DW: Planet of Fire)
 * The Sixth Doctor remembers his previous incarnation and the younger Peri encountering the older version of Peri defeating Zarl in Los Angeles in 2009. This is similar to MA: Cold Fusion, BFA: The Four Doctors and DW: Time Crash in which the Seventh, Eighth and Tenth Doctors respectively likewise remember the events portrayed from the perspective of their fifth incarnation.
 * The Sixth Doctor refers to Jamie McCrimmon and Zoe Heriot being returned to their native eras by the Time Lords with no memory of their adventures with his second incarnation, aside from their respective first encounters with him. (DW: The War Games)
 * Though it is not stated directly, the older Peri was presumably returned to Earth at some point after September 1984 in order to maintain the Web of Time. Otherwise, her presence would have affected the events of BFA: The Reaping and, by extension, BFA: The Gathering or perhaps even prevented them from coming to pass.
 * More than one version of a companion (Amy Pond) would later exist in DW: The Girl Who Waited.

For the Fifth Doctor and Young Peri

 * Peri and the Piscon Paradox takes place after PDA: Warmonger
 * Peri and the Piscon Paradox takes place immediately before DW: The Caves of Androzani

For the Sixth Doctor

 * Peri and the Piscon Paradox takes place after BFA: Her Final Flight
 * Peri and the Piscon Paradox takes place before BFA: I.D.

For the Older Peri

 * Peri and the Piscon Paradox takes place 25 years after DW: Planet of Fire