Collapse / Everything changes is the seventh level of Chapter 4.
Dialogue
Madame Vastra: As suddenly as the rollercoaster ride started, it stopped. With a thud and what sounded like a sigh we landed, and the TARDIS powered down. Looking back the TARDIS, the eternal "she", really didn't want us to land. It took the Doctors a full five minutes to get her to reboot, they didn't even have time to greet their latest incarnation who stood to one side shaken and confused. When the reboot was complete and the doors could open again, one of them said the fateful words "I guess we should take a look outside..."
Madame Vastra: As the first glimpse of light shone through the thinnest crack between the TARDIS doors the Doctors vanished. No sound, no fanfare, they were just gone. As we all looked around. Not believing what we had just seen, the doors opened wide and I heard two words...
?: "Hello Sweeties."