Doctor Who is getting a creepy new monster for episode 4.

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The iconic sci-fi series is currently filming in Cardiff, and bystanders outside of the Hadyn Ellis Building at Cardiff University on Tuesday received and advanced look at what's in store for episodes 4 and 5.

While the TARDIS deposited the usual suspects on the university lawn - the Doctor (Peter Capaldi), Clara (Jenna Louise Coleman), and Danny Pink (Samuel Anderson) - there was also someone else lurking around campus.

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A minutor like creature complete with lanky, clawed arms and a horned skull could be seen wander the set, and it looks like the monster may leave Twelve and his crew with a bit of an aging problem (see photo here).

"It appears Clara has been distracted by something earlier in the episode that's caused Danny to go old," tweeted a frequent Doctor Who set visitor.

Additionally, a voiceover overheard by fans gives a major hint at the main premise Steven Moffat scripted plot, according to Doctor Who TV.

"When you talk to yourself... what if the person you're talking to isn't really you?"

Find out how all the pieces fall into place when Doctor Who returns to BBC and BBC America later this year. Check out a scene from the upcoming season 8 premiere in the video below.

Tags: Doctor Who BBC BBC America television