Heather Lake was a human living on Earth in the late 20th century.
Her husband, Patrick Lake, told her and their daughter Annabel that he was an accountant. However, he was actually a spy working for MI6.
They moved to Prague so he could investigate Yuri Azarov. In November 1989, Heather and Annabel were kidnapped by Azarov. Here they met the Eleventh Doctor, who was also being held captive. They discovered the Golem of Prague and freed it from Azarov's control.
Later, the Mavora Queen destroyed the Golem after the rest of the Mavora Collective was freed. The Doctor sent Annabel to sleep to prevent the Mavora from feeding on her fear. While she was asleep, Heather touched the sphere of psychic metal that made Gerhard Frankel the original Golem in the 16th century. It transformed Heather into the new Golem, which destroyed the rest of the Collective. (COMIC: The Broken Man)