The Doctor said of the Cyberman: “Humans like all of you changed into empty, soulless shells.
“No feeling, no control, no way back. I will not lose anyone else to that,” as many viewers noticed a reference to past character Bill Potts (Pearl Mackie), who was defeated at the hands of The Cybermen.
One wrote: “BILL REFERENCES, THEY’RE CONNECTING TO PAST WHO. IT’S ALL COMING TOGETHER, THIS IS REALLY COOL #DoctorWho.”
Another echoed: ”Also I love the fact Thirteen is clearly still haunted by the fact she lost Bill Potts to the Cybermen and doesn’t want anyone else to end up the same. It’s all still fresh on her mind. #DoctorWho.”