Doctor Who is bringing back one of its scariest aliens - the Ood.

The fearsome creatures are returning for an episode in the fourth series of the hit BBC sci-fi show, entitled Planet of the Ood.

Viewers will discover the origins of the Ood, and see whether David Tennant's Doctor and his new companion Donna, played by Catherine Tate, become their friend or foe.

The Ood sport red mouth tentacles and a bald head and first appeared last year in an episode called The Impossible Planet.

Prosthetics experts were told to come up with "bald albino things with tentacles like a sea anemone rather than a mouth".

The creatures were recently voted the sixth most scariest Doctor Who villain, after the likes of the Daleks and the Cybermen.

Writer and executive producer Russell T Davies has described the Ood as "the most brilliantly made monster in the world", adding they look like "they're permanently throwing up. It's really disgusting".

Today he said: "We're delighted the Ood are making a welcome return to Doctor Who.

"They were last seen falling into a black hole back in series two and we think it's only fair for the viewers to find out what the Ood have to say for themselves. Donna is certainly in for a shock."

The fourth series will appear on TV screens in spring next year.

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