'Torchwood: Children Of Earth' is written and executive produced by Russell T Davies. It will star Captain Jack, played by John Barrowman, battling to save Earth along with his sidekicks Gwen and Ianto.
'Torchwood' started life as a BBC Three series before jumping to BBC Two. The third series comprises five hour-long episodes.
'Torchwood' fans were given a sneak preview of the new series in February when a 60-second trailer of 'Torchwood: Children Of Earth' aired on the show's website where an extended preview is now available.
'Torchwood' has proved a big hit with audiences in the US and is BBC America's highest-rated show.
The new television series follows last month's announcement of three new radio plays featuring the 'Torchwood' cast and characters, to be broadcast on Radio 4. The plays are written by three different authors -- Anita Sullivan, James Goss and Phil Ford.
For the new television series, Russell T Davies was lead writer on the first, third and fifth episodes. The second and fourth were written by John Fay. James Moran worked on episode three.
The elevation of 'Torchwood' to BBC One comes as sci-fi takes a knock on ITV. It was today confirmed that time-travelling dinosaur drama 'Primeval' has been cancelled.
Last month the BBC named 21-year old actress Karen Gillan as the companion for new Doctor Matt Smith. 'Doctor Who' returns to BBC One in spring 2010.