Required to capture a country of vast distances and multiple contradictions, American literature has tended towards the gigantesque: and stretching as it does to eight hours across two parts, Tony Kushner’s Angels in America is the Moby-Dick of American theatre, filled with massive ideas, images and language.

Perhaps no other play has such a range of tone. The through line is a family story with such compelling and emotional twists that it would not be out of place on peak-time TV. Joe, a young Mormon lawyer, is married to Harper, but there are tensions that are explained when Joe starts an affair with Louis, a court official, who has failed to find the courage to remain with Prior, his boyfriend, who, in 1980s New York, has become one of the first to be diagnosed with Aids.

But around a narrative backbone old-fashioned in everything except that most of the relationships are gay, the dramatist hangs plot lines ranging from the fact-based to the fantastical. The prevalence of angelic messengers has baffled some, but Kushner seems to be invoking both metaphorical divine spirits and specific ones: the Angel Meroni, whom Mormons believe to have appeared to the founder of their faith, and the huge statue of an angel that has stood above a fountain in Central Park since 1842, giving thanks for the clean water to the city.