Lindsay Duncan will star as the Time Lord’s companion in this year’s second Doctor Who special, the BBC has confirmed.

Lindsay, who is starring as Margaret Thatcher in the BBC Two drama Margaret, will play Adelaide – the Doctor’s cleverest and most strong-minded companion yet.

She will join David Tennant, who continues his role as the Doctor in the second instalment of four specials to be screened throughout 2009.

The second special will follow Planet Of The Dead, due to air this Easter on BBC One.

Lindsay, 59, said: “I’m thrilled to be involved in Doctor Who. I’ve never done anything like this before and I’m really looking forward to working with David Tennant and the Doctor Who team.”

The second episode is being written by executive producer Russell T Davies and Phil Ford. It is due to go into production in spring and will be screened later this year.

Russell said: “Lindsay is an incredibly talented actress and I’ve been an admirer of her work for some time.

“We are delighted to announce that she will be joining the team and playing the Doctor’s most strong-minded companion yet.”

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