The Four Doctors (audio story)

The Four Doctors was Big Finish's subscriber-free release for 2010.

Publisher's summary
The fifth incarnation of the Doctor has been allowed access to the Vault of Stellar Curios, where the biomechanoid Jariden are at least prepared to consider his warnings about dangerous temporal leakage. Suddenly, out of nowhere, the Daleks attack, unleashing a temporal maelstrom that will not only threaten the Jariden race, but will have dire consequences for the history of the Doctor himself.

Cast

 * Fifth Doctor - Peter Davison
 * Sixth Doctor - Colin Baker
 * Seventh Doctor - Sylvester McCoy
 * Eighth Doctor - Paul McGann
 * The Daleks - Nicholas Briggs
 * Professor Kalinda/Lady Cowen - Ellie Burrow
 * Colonel Ulrik/Whitmore - David Bamber
 * Professor Michael Faraday/Magran - Nigel Lambert
 * Roboman/Jariden Device - Alex Mallinson

Continuity

 * A Special Weapons Dalek (DW: Remembrance of the Daleks), the Dalek Prime (EDA: War of the Daleks) and the Robomen (DW: The Dalek Invasion of Earth) all appear.
 * The Fifth, Sixth and Seventh Doctors all previously met each other in BFA: The Sirens of Time. The Fifth and Sixth Doctors also met each other in CC: Peri and the Piscon Paradox. On that occasion, the Sixth Doctor disguised himself as a Piscon named Zarl so his younger self did not realise his identity. The Fifth and Seventh Doctors also met on at least two other occasions, namely in MA: Cold Fusion and prior to the events of BFA: The Veiled Leopard. Furthermore, the Eighth Doctor previously met his three immediate predecessors (as well as his first four incarnations) in EDA: The Eight Doctors. Given that the Seventh Doctor failed to recognise his immediate successor on this occasion, it is logical to assume that none of the first seven Doctors retained any memory of meeting their future self.
 * The Eighth Doctor remembers speaking to the Fifth Doctor over the intercom from the perspective of his younger self. This is similar to CC: Peri and the Piscon Paradox, NA: Cold Fusion and DW: Time Crash in which the Sixth, Seventh and Tenth Doctors respectively remember the events portrayed from the point of view of their fifth incarnation.

Fifth Doctor

 * The Four Doctors occurs after ST: Suspension and Disbelief
 * The Four Doctors occurs before BFA: Renaissance of the Daleks

Sixth Doctor

 * The Four Doctors occurs after BFA: Legend of the Cybermen
 * The Four Doctors occurs before PDA: Business Unusual

Seventh Doctor

 * The Four Doctors occurs after BFA: Last of the Titans
 * The Four Doctors occurs before DWM: Ground Zero

Eighth Doctor

 * The Four Doctors occurs after ST: The Sorrows of Vienna
 * The Four Doctors occurs before ST: Forgotten