Shoppers in Cardiff will have a sneak preview of life in the fourth dimension as filming of the new Doctor Who series starts this week.
Christopher Eccleston will become the ninth Doctor Who
The science fiction show, starring Christopher Eccleston as the latest reincarnation of the timelord, is being made by BBC Wales.
Singer and actress Billie Piper is appearing as the doctor's sidekick.
City centre streets are being closed off for filming on Tuesday and Wednesday for location work.
The new series, written by Queer as Folk creator Russell T Davies, will hit TV screens in 2005.
Eccleston, 40, whose previous credits include Jude, Shallow Grave and Our Friends in the North, recently said he wanted to bring more emotion to the lead role.
Billie Piper will star as Rose Tyler in the new series
As the ninth doctor, he will follow in the footsteps of the likes of William Hartnell, Paul McGann, Jon Pertwee, Tom Baker and Peter Davidson.
However, the run-up to the new series has been overshadowed by news that the Daleks will not be returning.
Earlier this month, the BBC confirmed that talks between the BBC and the estate of late sci-fi writer Terry Nation, who created the Daleks, broke down over issues of editorial control.
As Doctor Who's sworn enemies, the Daleks were voted the most evil villains on television in a vote by more than 3,000 GMTV viewers in 2003.
Doctor Who began in 1963, and seven actors played the doctor before the show was dropped in 1989.
Former pop star Piper will play Rose Tyler alongside Eccleston.
Antony Wainer of the Doctor Who Appreciation Society, said fans were very excited by her casting.