The elder statesman of American documentary, Frederick Wiseman, returns with an in-depth look at London’s great museum, home to a spectacular array of masterpieces.

Visitors, administrators and docents are all here. Wiseman burrows deep into this institution, as he has with many others. There’s no overarching narrative, so while it is never dull, this film doesn’t have the dramatic tension of last year’s splendid (and even longer) “The New Rijksmuseum.” But scenes like a curator describing a Camille Pissarro painting to a group of blind art lovers are so powerfully engrossing that explanation is superfluous.

Less tiring than a three-hour tramp through the halls, and considerably less expensive than a plane ticket, “National Gallery” gives the feeling of having seen everything there is to see.