During her first adventure with the new Doctor, Clara, who doesn't trust him, receives a call on her cell phone from Matt Smith's Doctor, who's in the middle of regenerating. He tells her that as much as she is scared about the regeneration, the new Doctor is even more so. After the call she will hug the new Doctor. Clips of the filming can be found on Youtube, though the audio is poor, can barely hear the voices.

In an episode titled "Ghost of Pompei" the Doctor will learn why he looks like some one he (DT's Doctor) met there once. The fact that Peter Capaldi appeared in Doctor Who before being the Doctor isn't being ignored but is explained. Said to be a cameo by a "fan favorite".

At the other end of the series, rumor has it that the Doctor finds Gallifrey in episode 11 and the Master returns in episode 12, with a new face too.