Backtrack (audio story)

 was the second story of The Tenth Doctor Chronicles, produced by Big Finish Productions. It was written by Matthew J. Elliott, performed by Jacob Dudman and Jon Culshaw and featured the Tenth Doctor and Martha Jones.

Publisher's summary
When the TARDIS crashes in the vortex, Martha and the Doctor find themselves on board the time-ship The Outcome, where the host offers temporal cruises at reasonable prices.

But time travellers must never cut corners. Dangerous forces have been unleashed, and Martha finds her medical skills put to the test as she deals with some lethal fall-out.

Time is running out, and the clock is ticking towards disaster!

Plot
to be added

Cast

 * The Doctor / Narrator - Jacob Dudman
 * Nathan Hobb - Jon Culshaw

Uncredited cast

 * Martha Jones - Jacob Dudman (BFX: The Tenth Doctor Chronicles)

Worldbuilding

 * The Doctor keeps all his comics in the Number Three hold of the TARDIS, including the complete run of Whizzer and Chips.
 * The Doctor is trying to take Martha back to the Royal Hope Hospital.
 * Nathan Hobb bought a Magnetic Quantum Field Generator from the Maldovarium for his time ship, The Outcome.

Story notes

 * Martha is currently on the "one trip" that the Doctor promised her at the end of TV: Smith and Jones. This trip has turned into "several trips" which will end in TV: The Lazarus Experiment when Martha becomes an official companion.

Continuity

 * The Doctor and Martha's conversation about the Time War is mentioned. (TV: Gridlock)
 * Martha is still on her "first trip". (TV: Smith and Jones)
 * The Doctor states that if time collapses, there will be no Shakespeare (TV: The Chase, Smith and Jones; AUDIO: The Time of the Daleks; PROSE: Apocrypha Bipedium, All Done with Mirrors) and no New New York. (TV: New Earth, Gridlock, AUDIO: Tales from New Earth)
 * The Doctor mentions previously encountering a travelling time travel company. (TV: Delta and the Bannermen)