Ood Sigma, played by Paul Kasey, has been spotted on location in Cardiff for this year’s second special episode!

Last seen in Series 4’s Planet of the Ood, the Ood was pictured on set by various fans in the early hours of this morning.

Filming for the episode, which will star Lindsay Duncan as Adelaide, the Doctor’s most ’strong-minded companion yet’, is currently taking place in the Welsh capital. Duncan and David Tennant were also on set.

It’s unknown why Ood Sigma was there, or if any other Ood will be appearing in the episode, which is expected to air on Christmas Day 2009. Perhaps it has something to do with the Tenth Doctor’s upcoming regeneration?

Thanks to Scooty of the Doctor Who Forum for the picture!