Collins’s remarkable stage debut had the audience holding its breath in reverential concentration.

Emily in Paris becomes Lily in London. Or to be even more precise, Irene in Barcelona, as Lily Collins, star of the lovably daft Netflix smash hit, makes her stage debut in Bess Wohl’s grippingly classy two-hander about an American woman on a “bachelorette weekend” in Spain. These are among the best 90 minutes of theatre I have seen all year and the applause at the play’s end went on for so long that Collins began to look bashfully embarrassed.

With her trailing blonde hair and sparkly silver jumpsuit – Irene is another fashionable American in Europe – she stumbles into the “muy lindo” apartment of older Spanish man Manuel (Money Heist star Álvaro Morte), whom she has met in a bar. Irene is playful, skittish and drunk and Manuel – or Manolo, as she keeps calling him – is keen to move things into the bedroom. Tiny wrinkles of doubt begin to creep in, for us as well as Irene: why don’t the flat’s taps work? And why does Manuel keep glancing anxiously out of the window?

It says a lot about us – as humans, as well as consumers of a culture in which traditionally attractive women are not treated well in strangers’ apartments – that we are Expect mood swings and something bad to happen to Irene. It’s not, but this is the kind of rare and fascinating work about which the fewer details we know in advance, the better, to enjoy the fluctuating tone as it unfolds.

This is Collins’s remarkable stage debut, conveying a compelling blend of intertwined weaknesses and strengths. Irene’s slurred speech masks – less professionally – deep whirlpools of uncertainty and Morte’s Manuel becomes impatient with the lies she is clearly telling herself. However, self-deception does not always work in one way and this elegant Spaniard has been forced into a reckoning with his own past.

Barcelona works great because every element is like peeling back the layers of a very large onion. Frankie Bradshaw’s design, luxurious and sumptuous on the surface, begins to offer disturbing clues the longer we study it. Director Lynette Linton is at the peak of her career with a work that has no scene changes, exits or entrances to change the mood. There is perfect shading and pacing as late night gradually turns to early morning and both Irene and Manuel realize they have important decisions to make. Wohl’s script maintains a light touch while embracing the heavy geopolitical theme of America’s self-proclaimed global superiority.

It’s rare that a play induces in its audience a reverential hush of concentration, with several hundred spectators seeming to sit without the slightest shuffling and hold their breath anxiously as the drama unfolds. This is the special sort of thrill that only live theatre can offer and Barcelona does so triumphantly.