The claim to theatrical fame of the Long Island hamlet of Yaphank has thus far rested with PG Wodehouse, who included the town in his lyrics for Jerome Kern’s satirical hymn to the simple life, “Bungalow in Quogue.” But in the new play by current Tony Awards nominee Bess Wohl (“Grand Horizons”), now playing at the Old Vic in London, the area takes on a starkly different hue. The intriguing, darkly suggestive title “Camp Siegfried” produces an immediate frisson of history that underpins the play and its strengths. But there are moments when Wohl’s handling of that also leads to its weakness.

The tension between suggestion and literal depiction is neatly exemplified by Rosanna Vize’s set, which for the most part consists solely of wooden slats, deftly lit by Rob Casey, hanging across the stage. This acts as a screen for the occasional burst of Tal Rosner’s black-and-white video footage of healthy-looking children, but more often serves as an elegant symbol of the woods where the camp is set.

It’s here in the summer of 1938 that Luke Thallon’s strapping, healthy boy meets Patsy Ferran’s studious, Latin-loving girl (named only in the script as “Him” and “Her”). Not only is she 16 and he 17, but he considers himself both older and wiser and sets about telling her what to do at the camp where he has been coming for years but where she is a newcomer.

As in the extraordinary real-life history of the camp, they are both German children who, we gradually understand, are being indoctrinated. But unlike in “The Sound of Music,” they are being actively encouraged not only to fraternize with each other after dark, but, we slowly discover, to breed. The camp is inculcating them with German values, especially those of the Nazis.

Wohl’s study of the effects of indoctrination, and the way teenagers’ thoughts, doubts and fears are hung upon their relationships, offers plenty of insight. In successive short scenes, she engagingly teases out the stages of their relationship from attraction through suspicion to connection and beyond as the two look at themselves, at each other, and at their future as increasingly guided by the camp’s ideology.

The more layered the writing, the stronger it is. But in the latter part of the play, overstatement gets the better of Wohl. Her thesis of the obvious dangers of the era, which the characters don’t recognize but which the audience does, grows less effective as the play proceeds. And the parallels with the present (the play was written during Donald Trump’s re-election campaign) feel too underlined. Despite Ferran’s faultless performance, her two long speeches, one political, one personal, are explicit when something less so would have more power.

Director Katy Rudd occasionally pushes her actors a little hard: At the final preview, it felt that a little more relaxation would allow the play to breathe. But she has cast it brilliantly. Last seen being ideally and intellectually smug in Tom Stoppard’s “Leopoldstadt,” rising star Luke Thallon transforms himself here into a buoyant, perfect gilded youth, chopping logs and glowing with self-assurance. A sense of zeal shines off him. He’s particularly good at indicating while not actually showing the cracks beneath his surface confidence.

He is ideally matched by the magnetic Ferran who, already armed with one Best Actress Olivier for her revelatory Alma in “Summer and Smoke,” was previewing as Honey on Broadway in Joe Mantello’s “Who’s Afraid of Virginia Woolf?” when COVID-19 scuppered the production. Much of her vivid stage power derives from controlled understatement. Her character is as nerdy as she is nervous, but Ferran keeps her physicality taut rather than taking the obvious choice of trembling. By never resorting to “display acting” and instead giving space for the text do the work, she effectively adds an entire thoughtful layer to the character that you can feel the audience homing in on.

Ultimately, despite its many felicities, as the evening progresses you realize you’re never in doubt about what the author wants you to think. That’s great in a thesis, but less so in a play. As Ferran and Thallon beautifully show, sometimes the less you explain, the stronger the drama.

‘Camp Siegfried’ Review: Bess Wohl’s New Play at the Old Vic in London

The Old Vic, London; 1,067 seats; £90 ($124 top). Reviewed Sept. 16, 2021, opened Sept. 17. Running time: 1 HOUR, 30 MIN.

  • Production: An Old Vic production presentation of a play in one act by Bess Wohl.
  • Crew: Directed by Katy Rudd. Sets and costumes, Rosanna Vize; lighting, Rob Casey; sound, Ian Dickinson for Autograph; video, Til Rosner, production istage manager, Tamsin Withers.
  • Cast: Patsy Ferran, Luke Thallon.