Maxine Peake and Matthew McNulty star in the latest two-part adaptation of the 1950s novel about the rise of amorous Joe Lampton, who is willing to do anything to get to the top.
According to the Daily Mail, the last-minute withdrawal of the show was down to a legal challenge. The John Braine-penned story was previously turned into a film in 1957, while Thames produced spinoff comedy series Man At The Top in the 1970s.
Braine's family and widow approved the BBC adaptation, but a rival producer has claimed ownership of the screen rights.
A BBC rep said: "Transmission of Room At The Top has been postponed while we address a potential contractual issue which has emerged in the last few days." A repeat of Fanny Hill aired instead last night.
The author's son Tony said: "My mother has the rights to the book and she was looking forward to watching the drama on Thursday night. We just heard that it won't be on and it's disappointing. The objection is nothing to do with the family members."
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