“The Children” begins as what seems like a small, slow domestic drama about three aged friends in an English seaside cottage, but turns into an unsettling meditation on some very large themes — life, death, the responsibility of one generation to the next, the poisoning of the planet.

Playwright Lucy Kirkwood roots her larger themes in concrete details, a series of startling surprises, and some resonant metaphors, woven into nearly two hours otherwise filled with seemingly idle small talk. Her approach might try the patience of the average attention-deficit New Yorkers, but “The Children” hits home by the end.

Rose (Francesca Annis) is paying a visit to Hazel (Deborah Findlay) and her husband Robin (Ron Cook.) The first big surprise — they were all nuclear physicists, who worked on a nearby nuclear power plant, which was the site of a recent disaster similar to what occurred for real in 2011 in Fukushima, Japan. There was a nuclear meltdown caused by two natural catastrophes (a tsunami followed by an earthquake) and one manmade one: an error in the design of the reactor – a reactor that all three characters helped create.

The couple was forced to move out of their home, inundated with water and radiation, and take up residence in their cottage, not far from the “exclusion zone,” and they live with plenty of problems – a lack of electricity, faulty plumbing, the danger of getting sick from radiation.

Now Rose is visiting them, after (another surprise) not having seen each other for nearly 40 years. If they haven’t grown apart in that time, it’s because they were never fond of one another to begin with. There is palpable hostility

“If you’re not going to grow, don’t live,” the fastidious Hazel says several times to the still-adventurous Rose, and if we think at first this is one old lady talking philosophically about aging with her long-time friend, it slowly becomes clear that Hazel, consciously or subconsciously, means this literally; she wishes Rose dead. Rose far more consciously wishes Hazel dead too.

Their resentments are tied up with another surprise revealed in stages – Hazel and Rose haven’t seen each other for decades, but Rose and Hazel’s husband Robin were lovers before Robin got married….and afterwards too…as recently as a few years ago.

Rose has come for a purpose – but it’s not what you (or the two other characters of the play) may initially suspect.

“The Children” seems designed to keep us at a distance – Miriam Buether’s set is placed within a box that’s placed upon the stage, as if in a picture frame. Perhaps this is a metaphor for the characters’ increasingly constricted lives. The title is yet another metaphor; there are no actual children in the play. But under the direction of James Macdonald, the three veteran British actors bring credible characters to life. It helps too that much of the squabbling and banter is amusing. They even let loose to James Brown at one point.

But now and then, they speak lines that sound like anthems for a generation that needs to wake up, such as when Rose says:

“I think I’ve grown up a lot. Because I understand, I do understand now, that for the world not to…completely fall apart, that we can’t have everything we want just because we want it.”

Despite Hazel’s admonition to grow or die, Rose has in fact grown. But that doesn’t mean she won’t die.

The Children
Written by Lucy Kirkwood; Directed by James Macdonald
Scenic and costumes design by Miriam Buether; Lighting and projection design by Peter Mumford; Sound design by Max Pappenheim; Wig design by Carole Hancock
Cast Francesca Annis, Ron Cook and Deborah Findlay
Running time: one hour and 50 minutes, with no intermission.
Tickets: $60 to $149
The Children is scheduled to run through February 4, 2018