Image copyright Helen Maybanks Image caption Andrew Garfield as Prior Walter in Angels in America

Plays don't come much more epic than Angels in America.

Set amid the Aids crisis in 1980s America, Tony Kushner's "gay fantasia" lasts roughly the same duration as a flight from London to New York.

Over eight hours, it packs in angelic visitations, burning books and surreal trips to icy continents and, of course, heaven.

And let's not forget a stellar cast that includes Andrew Garfield, Denise Gough, Nathan Lane and Russell Tovey.

After weeks of previews, the play officially opened at the National Theatre in London on Thursday.

Image copyright Helen Maybanks Image caption James McArdle (Louis) and Andrew Garfield (Prior)

Spider-Man star Garfield told us after the show: "You don't often get to work on a character like this or on a story that has so much humanity in it.

"It's the whole human experience in one seven and a half hour play. No one would turn that opportunity down."

The critics seem to love it, with four and five star reviews appearing on Friday morning.

Here are eight reasons why Angels in America is such a heavenly show.

It may be long, but it flies by

Image copyright Helen Maybanks

On Thursday, both parts of the play played back to back - and lasted seven hours and 32 minutes.

Part one - titled Millennium Approaches - kicked off at 13:00, but it wasn't until after 23:00 that the second part - Perestroika - had reached its emotional climax.

But it never dragged. Much of the interval chat was about how quickly it seemed to go.

The cast may disagree.

Speaking after the show, Russell Tovey admitted: "On a two-show day, it's insane. It's like a 12-hour Zumba class!"

It's like binge-watching a box-set

Image copyright Helen Maybanks

The way the play is broken up gives it an episodic feel. Each part has two 15-minute intervals.

That makes watching the play feel a bit like you are working your way through a TV box-set.

With plenty of loo and coffee breaks.

Andrew Garfield's searing performance

The ex-Spider-Man is unforgettable as Prior Walter, a man who discovers he has Aids and is then abandoned by his boyfriend Louis Ironside (James McArdle).

We see him early on as an elegant drag queen, later he's a spectral hooded figure dressed top to toe in black.

In the harrowing hospital scenes, he can switch from rage to despair in the course of a single line.

Back in January, Garfield found out about his Oscar nomination for Hacksaw Ridge while he was starting rehearsals for Angels in America.

It would be astonishing if he's not nominated for more awards for this performance.

The rest of the cast are pretty amazing too

Image copyright Helen Maybanks

Nathan Lane plays foul-mouth lawyer Roy Cohn who is in denial about his sexuality. Told by his doctor that he has Aids, he storms: "No. Aids is what homosexuals have. I have liver cancer."

Tovey plays Joe Pitt, a closeted gay Mormon Republican whose Valium-addicted wife Harper is played with gusto by the Olivier-winning Denise Gough.

McArdle is excellent as Prior's tormented lover, as is Nathan Stewart-Jarrett as hospital nurse Belize.

With more than 30 characters in this play, all of the main cast play multiple parts and it's fun to try and spot them under the costume changes.

The director knows how to make a hit

Marianne Elliott is the award-winning talent behind the National Theatre's West End hits War Horse and The Curious Incident of the Dog in the Night-Time.

Enough said.

Angels is spectacular, yet intimate

Image copyright Helen Maybanks Image caption Denise Gough and Nathan Stewart-Jarrett in a fantasy Antarctic

The story begins quite modestly, with a simple revolving set showing us how the lives of the main characters connect.

Later it all goes much larger scale and a lot more surreal.

We get a fantasy Antarctica - complete with falling snow - and a neon ladder that ascends to a heaven filled with angels.

Yet many of the most memorable scenes are the intimate ones where Prior Walter and lawyer Roy Cohn are sick in their hospital beds and visited by both the living and the dead.

It tackles a serious subject with a lot of humour

Image copyright Helen Maybanks Image caption As foul-mouthed Roy Cohn, Nathan Lane gets many of the best lines

Angels in America had its British premiere at the National Theatre in 1992 (with a cast that included James Bond actor Daniel Craig).

The play is set in New York in the mid-1980s when Ronald Reagan was starting his second term as president and the world was in the grip of the Aids crisis.

While there is much that is upsetting, Kushner's script is packed with zinging comedy lines.

"It's very funny," said Garfield after the show. "You need to laugh to keep from crying in a situation as devastating as these characters are going through.

"It was amazing putting it in front of an audience for the first time because we were all surprised how funny it was.

"On the first preview it was shocking how many times we had to stop for the audience laughing."

The angel really takes flight

You won't forget Amanda Lawrence's Angel in a hurry.

She crashes dramatically through Prior's apartment ceiling on massive wings that are operated - War Horse style - by six people.

She flies, she swoops and she even has sex with Prior.

Little wonder he later introduces himself to Harper Pitt as "an angel-ologist".

Angels in America: A Gay Fantasia on National Themes is at the Lyttelton Theatre until 19 August.

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