The deal for 'Desperate Housewives', which along with 'Lost' is distributed by Buena Vista International Television, is understood to have cost Channel 4 around £900,000 an episode, totalling over £40m over the course of the next two years.
Channel 4 did have exclusive negotiating rights to 'Lost' and 'Desperate Housewives' after screening the first two series of each show in the UK, but these broke down prompting Buena Vista to open them up to competitors.
It is speculated in the media that the £40m deal for 'Desperate Housewives' signals a period of unease for Channel 4 in fending off rivals for its top-rated imports.
Channel 4 is set to face a similar battle hanging on to summer scheduling stalwart 'Big Brother', with ITV understood to be keen to take the show after the existing contract runs out at the end of next year's run. There is speculation that it could be asked to pay as much as £70m or nearly double what it currently pays for the reality hit.
Although the loss of 'Lost' will have come as a blow to Channel 4, the show, about a group of plane crash survivors on a mysterious island, shed around 4m viewers during the course of the second series.
Its decamping to Sky is likely to result in more viewers peeling away as happened when the station won '24' from the BBC.
'Desperate Housewives', which stars Teri Hatcher, Marcia Cross, Felicity Huffman and Eva Longaria, also lost viewers, but Channel 4 is understood to rate the show's long-term prospects highly.
Latest evidence from the US confirms that the 'Desperate Housewives' brand does indeed remain strong. A PC game version of the show, which was met with derision when released last month, was recently named the sixth most popular PC game in the US.
'Lost' has just begun its third series run on ABC Network in the US and is due to start its UK run on Sky One next month. Sky will also make it available on its broadband and mobile platforms.
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