As "Doctor Who" season 8 filming moves to episode 5, "Sherlock" fans may recognize a familiar name.

Spoilers confirm that in addition to a new special guest star in "Doctor Who" season 8 episode 5, it is being written by Steven Thompson, who has written three episodes of "Sherlock."

This is also the episode that will introduce Ms. Delphox, an other-worldly banker played by Keeley Hawes ("Line of Duty").

“I am delighted to join Doctor Who and to be working with this incredible team. Ms. Delphox is a great character and someone I’ve had a lot of fun playing," says Hawes according to Doctor Who TV.

From the filming set photos from "Doctor Who" season 8 episode 5, we also get a nice glimpse of Peter Capaldi's costume in action, as well as guest star Jonathan Bailey, who appears to be playing a cyborg of some kind.

Someone who's distinctly missing from the set photos is newcomer Samuel Anderson as Danny Pink, who has been at the center of a lot of rumors as of late.

The strongest rumor is that Danny Pink could be a new Master on "Doctor Who."

Given the events of "The Time of the Doctor" and "The Day of the Doctor," it would make sense plot-wise for Gallifrey to dispatch Time Lords to check out the universe that once tried to destroy them.

Danny Pink also wears a wrist watch in the official promotional photo, and since Derek Jacobi's Master stored his true self in a pocket watch, some believe it is a hint at him being The Master.

There are also theories that Steven Moffat is attempting to recreate the beginning of "Doctor Who" by including two Coal Hill School teachers in Danny and Clara.

Do you think Danny Pink could be the new Master on "Doctor Who?"