Doctor Who will take a break in 2009. Season 4 will air from March to June 2008, to be followed by a Christmas Special. However, there will be no regular series in 2009, only three more specials (one of which will presumably be at Christmas). Season 5 will then air in Spring 2010.
The move, which is somewhat unorthodox, is believed to be due to the BBC's keeness to keep both Russell T. Davies as producer/head writer and David Tennant as the Doctor. Davies had been heavily rumoured to step down at the end of Season 4, possibly in favour of Stephen Moffat or perhaps Paul Cornell, but will now stay on and write the TV specials plus work on Season 4. Although Tennant is also believed to be staying on, the BBC press release failed to confirm this. Tennant will spend his 'gap year' touring with the Royal Shakespeare Company in a production of Hamlet alongside Patrick Stewart (the Doctor and Picard on stage together = lots of SF fans in the audience). It is also speculated that the BBC will use the time to prepare the show for filming in HD. The BBC wants to get its entire output in HD by 2010.
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The Internet briefly exploded last week after Jamie Bamber (Apollo) claimed that the fourth and final season of Battlestar Galactica had been split into two ten-episode halves which would be shown a year apart starting in March 2008 and March 2009 respectively. According to Ronald D. Moore's wife on the Sci-Fi Channel Forum, this was a joke that was taken out of context. However, it's interesting that the fans so readily believed that the SFC would take such a crazy step.
Season 4 was previously said to be set to air in January 2008, although some vague rumours have suggested this may be put back to March. The season will air straight through, possibly with a brief mid-season break. Before Season 4 airs a special two-hour TV movie called Razor will air on the SFC on 24 November 2007. This TV movie takes place in late Season 2 but features extensive flashbacks to the history of the battlestar Pegasus. Michelle Forbes has resumed her role as Admiral Cain and the movie apparently features the most extensive CGI sequences done for the show yet. Some characters and storylines will play a role in Season 4 of the series. An extended version of the movie (15-20 minutes longer than on TV) will be released on Region 1 DVD on 4 December. UK release and broadcasting details are not known at this time. The movie will be preceded by 'webisodes' depicting the First Cylon War. The webisodes will be included on the DVD release.
At this time Lost Season 4 does not have a specific airdate, only that it will start in February 2008 on ABC and run for 16 episodes. Heroes Season 2 will commence airing on NBC on 24 September 2007. The new version of The Bionic Woman will commence airing on 26 September 2007 (after the pilot episod was leaked onto the Internet two months earlier; the broadcast version will be very different to the leaked version, apparently to the extent of substituting one of the lead actors).