Stanley Tucci won a Golden Globe for his role in Conspiracy

The drama, its title referring to the average weight of the human brain, features Tucci as a neurosurgeon who has to cope with a deteriorating mind.

The BBC refused to disclose how much it had spent to buy the programme, but it denied press speculation that the figure was in excess of �5m.

The 13-part series will be screened on BBC One in 2007.

"It's an intelligent, stylish, distinctive drama," said a BBC spokeswoman.

'Highly regarded'

The programme was "one of the most highly regarded pilots" shown to foreign broadcasters at recent screenings in Los Angeles, she added.

Several other television companies are understood to have bid for rights to show the series following the convention.

The BBC will be able to make back some of the money it spent on the programme by selling it to other channels for repeats, said the spokeswoman.

In recent years, the BBC has largely stopped showing imported US dramas during peak viewing hours.

But programmes such as Lost, CSI and Desperate Housewives regularly appear amongst the top 10 programmes on Channel 4 and Five.

Stanley Tucci won a Golden Globe in 2002 for his role in the BBC and HBO drama Conspiracy, which looked at how the Nazis planned the Final Solution during World War Two.

He will be joined on Three Pounds by British actress Indira Varma, who was recently seen in BBC Two's comedy series Broken News.