Lucy takes over from Sam Wollaston who is moving to G2 to become a features writer, and will report to acting TV editor Lanre Bakare. She starts on Monday 17 September.
As TV critic, Lucy will be writing four times per week - reviewing the latest and most popular releases.
Lucy Mangan said: “It’s a brilliant time to be a TV critic - we’re in a golden age of bold and diverse programming that is setting new boundaries all the time. I’ll be casting a critical eye on the latest developments, the popular long-runners and ensuring Guardian readers have the reviews they need to make their best TV choices.”
Lanre Bakare, The Guardian’s TV editor, said: “Lucy is a brilliant writer who Guardian readers know and love. Her reviews will be insightful, informative and entertaining. I’d also like to thank Sam Wollaston who has been a stellar TV critic and covered TV’s second golden age in his own characteristically witty way.”