Time Zombies, a not-quite-paranoid-enough android and a big friendly button
Big bruv, kid bruv and robo bruv are wielding an illegal magno-grab to salvage the not-exactly-derelict spacecraft that is the TARDIS. Coincidentally, in an effort to make peace between his companion and his timeship, The Doctor has just deactivated the shield oscillators and given Clara the reins, which gets them sucked straight into the salvagers’ junk hole.
With its oscillating engine bits damaged, the TARDIS is now destined to self-destruct. Plus, it’s filling up with poisonous fumes and Clara has been left to roam the TARDIS innards on her own. Plus, time zombies have suddenly appeared in there as well and are out to get anything un-zombied.
A race against the clock thus starts, as The Doctor must enlist the services of the three bruvs who got them in this jam in the first place, to travel deep into the heart of his timeship and save both it and the impossible girl.
And here’s a side-by-side comparison of the two telescopes, in Tooth and Claw and this one, respectively: