Upon arriving at the university, Bill Potts saw the Twelfth Doctor and Nardole running through it. She secretly followed them, until they arrived at a mysterious vault. Bill accidentally made a noise while in the vault, so she left.
Later, the Doctor ran across the courtyard, with Bill after him, to check out that puddle. That evening, that same sentient puddle, taking the form of Heather, confronted Bill outside the university building, having chased Bill from her flat. She immediately ran up to the Doctor's study. (TV: The Pilot)
After the Doctor's lecture on crop rotation became about space, Nardole strolled with him through the courtyard on the way to the vault, making the suggestion that the Doctor missed going to space. (TV: Oxygen)
While the Doctor and Petra dealt with an inter-dimensional creature, students across the quadrangle filmed the incident on their mobile phones. The Doctor captured the creature in a Polaroid photograph. (AUDIO: Dead Media)