Thinking empathic psychic Emma Grayling may be able to shed some light on Clara, the Doctor goes to 1974, where Emma and her future husband Prof. Alec Palmer are investigating a ghost known as the Witch of the Well, in Caliburn House. After the house grows cold and the message "help me" appears, the Doctor borrows Alec's camera and uses the TARDIS to take pictures of the mansion's location throughout time. Thanks to this, the Doctor learns it's not a ghost in the pictures, but a time traveler named Hila Tukurian who got stuck in a pocket dimension; she's running from a hideous creature. The Doctor quickly constructs a device that amplifies Emma's psychic abilities, creating a portal to the pocket dimension. Emma cannot keep the portal open long enough for the Doctor to escape. Clara manages to persuade the TARDIS to briefly fly through and collect the Doctor, who hangs on to the exterior and is dragged back to reality. The Doctor explains Hila is a descendant of Emma and Alec. The Doctor realises another creature was inside the mansion and its mate was the creature in the pocket dimension; he quickly returns to save it.