The Top of the Tree (audio story)

 was the second story of The Eleventh Doctor Chronicles, produced by Big Finish Productions. It was written by Simon Guerrier, performed by Jacob Dudman and Danny Horn and featured the Eleventh Doctor and Kazran Sardick.

Publisher's summary
On one of their annual jaunts, young Kazran Sardick and the Doctor find themselves in trouble when the TARDIS is tangled in the branches of a very strange, very large tree.

They emerge into a habitat where myriad species fight for survival: an ecosystem of deadly flora and fauna, along with a tribe of primitive humans.

This is a mystery which can only be solved by climbing. But what will they find at the top of the tree?

Plot
In the TARDIS, the Doctor and Kazran pick up an untranslatable signal which they follow through the Time Vortex. They arrive in a giant tree and, upon exiting the ship, fall from a great height onto soft moss. Kazran is knocked out and the Doctor assesses his injuries and examines a pod which starts to swallow his arm. When Kazran awakens, he tries to use a branch to force the pod open but is instead stuck himself. They fall and are freed by a child of humans who speak a proto-language.

The Doctor and Kazran climb the tree and reach a village where they meet people wearing the remains of space suits and other signs of advanced technology. Awkward remembers stories of how her ancestors arrived here and learnt to live in harmony with the tree and tells them that there is something down in the dark. The Doctor and Kazran descend with some of the people, passing large insects fleeing upwards on the way, and Bluebeard is killed by a dark liquid. They return to the village and the Doctor realises that the liquid is tree sap.

The mothers and the young climb first so that the sap falls on the elderly. The Doctor and Kazran reach the top of the tree and find that it opens out into space and, warming up because of the nearby star, the tree is sending a signal to space insects to let them know to lay their pods. This is the signal that the TARDIS picked up. The Doctor dives into the sea of sap and manages to find the TARDIS in the nick of time; the ship takes him to the Sisters of the Infinite Schism for healing and, after a few months, he returns to the tree and saves Kazran and Awkward's tribe as the sap rains down on them.

The Doctor pilots the TARDIS to the nearby planet of Ember, Kazran's homeworld, where they will be safe. Kazran realises that the tribe are his ancestors and that he has helped to found his own society, which he almost thinks would make his father proud. Whilst he will never be able to tell his father, the Doctor says that it is something he can tell Abigail.

Cast

 * The Narrator / The Doctor - Jacob Dudman
 * Kazran Sardick - Danny Horn

Worldbuilding

 * Kazran and the Doctor mention a prior encounter with the Draconians.
 * The Doctor mentions Müller and his pooh-pooh and ding-dong theories.
 * The Harak All-Happenstance Suit is meant to survive anything. The patent is fiercely protected, so they are only ever found on Mac Cárthaighs.
 * Kazran mentions his father, Elliot Sardick.
 * Perihelion is nearing.
 * The Doctor visits the Sisters of the Infinite Schism.

Continuity

 * Kazran mentions fishing for sharks. (TV: A Christmas Carol)
 * The Doctor goes to the Sisters of the Infinite Schism to heal and notes that he must remember them. He would later take River Song there after she used all her regeneration energy to save his life. (TV: Let's Kill Hitler)