Ex-Doctor Who companion Sarah Jane Smith will return in the new series of the sci-fi show, it was revealed as the Doctor's new costume was unveiled.
Popular 1970s character Sarah Jane, played by Elisabeth Sladen, will join new Doctor Who actor David Tennant.
However Rose, played by Billie Piper, will remain the Doctor's full-time companion throughout the new series.
The Doctor's "striking" new outfit consists of a striped suit, trenchcoat and trainers.
'Timeless and modern'
Tennant said: "I think we've come up with something distinctive that's both timeless and modern, with a bit of geek chic and of course, a dash of Time Lord!
"Most importantly Billie tells me she likes it - after all she's the one who has to see me in it for the next nine months."
Casanova star Tennant replaced Christopher Eccleston in the lead role, appearing briefly at the end of the last BBC series in June.
Piper said she was "thrilled" to be playing companion Rose again.
"We plan to make series two even bigger and better and challenge the viewers' imaginations like never before," she said. "Wait until you get a load of the new doctor!"
The character Sarah Jane previously appeared in the series from 1973 to 1976, alongside Doctors played by Jon Pertwee and Tom Baker.
Sarah Jane originally appeared in Doctor Who from 1973 to 1976
A journalist with outspoken feminist views, she was given robot dog K-9 as a goodbye present from the Doctor and appeared in spin-off pilot show K-9 and Company.
The new 13-part series will also feature Buffy the Vampire Slayer star Anthony Head and an episode will be written by comic Stephen Fry.
Penelope Wilton will return to play Harriet Jones in a Doctor Who Christmas special, as the alien Sycorax threatens the earth in an episode currently being filmed in Cardiff and London.
The Cybermen will return in the new series, and the Doctor and Rose will meet Queen Victoria and an evil race of Cat Women.
We can promise new thrills, new laughs, new heartbreak and some terrifying new aliens
Russell T Davies, executive producer
Coyote Ugly star Adam Garcia will make an appearance and further episodes will be written by Russell T Davies, Mark Gattis and Tom Macrae among others.
Davies, who remains the show's executive producer, said: "We were delighted and honoured by the first series' success, and we can promise new thrills, new laughs, new heartbreak and some terrifying new aliens."