The closing credits of National Treasure (Channel 4, Tuesday) contain the usual disclaimer that any resemblance between its characters and real people is merely coincidental. Well, coincidental maybe, but also entirely inevitable — because this is a drama based on Operation Yewtree.

With its choice of subject matter, a cast including Robbie Coltrane and Julie Walters and a script by Jack Thorne (author of the all-conquering Harry Potter and the Cursed Child), the series is clearly intended as an Important Piece of Television.