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Collision Course was the sixth and final story in the audio anthology The Legacy of Time, produced by Big Finish Productions. It was written by Guy Adams and featured Tom Baker as the Fourth Doctor, Louise Jameson as Leela and Lalla Ward as Romana.

Publisher's summary[]

Fallout from the temporal distortions has now reached Gallifrey. To find the cause, Leela and Romana remember travels with the Fourth Doctor to the same world, at different times. The enemy is revealed, and it may take more than one Doctor to prevent the destruction of everything!


to be added




  • Romana acts as the captain of the prototype TARDIS while the Third, Fourth, Fifth, Sixth, Seventh and Eighth Doctors replace the pilots; the First, Second and Tenth Doctors take care of the residual backlash.

The Doctor[]


  • The prototype TARDIS is not dimensionally transcendental.
  • The Tenth Doctor comes up with the term "guardfox waveforms" to make his contributions and that of the first two Doctors sound important. The First Doctor calls him on his bluff.
  • The Sixth Doctor has to adjust for temporal drift.
  • The Third Doctor hands off the helmic regulator to his fifth self.
  • The Doctors manage to increase power to the temporal buffers by extracting it from their own TARDIS, through remote power transfer. They need to do so to avoid a temporal shockwave.
  • The Eighth Doctor has to instruct his third self to look between the bakelite TV set and the Goblin Teasmade to find the power link-up in the Seventh and Eighth Doctor's control room. Though the Third Doctor does not hear, he finds it anyway.



External links[]