Clips

The Heart of the TARDIS
The Doctor, thinking they are going to die, asks Clara to explain who she is and how she could have died twice before. Clara doesn't understand, and the Doctor realises she has no knowledge of their previous encounters and is simply a young woman. The Doctor and Clara then leap across the chasm, believing that it is an illusion the TARDIS is using to scare off others. Reaching the engine room, they find the engine has exploded but the TARDIS has placed the room in time stasis as a safety measure. Clara looks at her hand, the burn marks formed into words - "big friendly button".

Time Zombie Attack!
The TARDIS is picked up by an intergalactic salvage crew, accidentally knocking Clara into the depths of the TARDIS. Needing help to rescue her, the Doctor promises the Van Baalen brothers the salvage of a lifetime. To ensure cooperation, the Doctor locks everyone in and sets the self-destruct to go off in 30 minutes. As if that wasn't bad enough molten time zombies are attacking!