There's been a murder in the Big Brother house, only it's not called the Big Brother house, because the fictional TV show is called House Arrest. The plotting is clever, keeps the reader in suspense, but apart from the inevitable, cynical old cop, the characters are not sufficiently different to always know who is speaking.
But my main objection to the book is nothing to do with how well or badly it's written. It's just that, I thought of it first! Big Brother was obviously asking for a murder, or even several! I'd conceived a parody of an Agatha Christie style murder mystery, but hadn't committed anything to paper before Ben Elton came along with Dead Famous... dammit!
Is it worth reading? Maybe not. This isn't Ben Elton's best book and Big Brother became a true parody of itself long ago so, really, who cares?