LONDON, July 23 — The madman in charge doesn’t know what he’s doing. Nobody trusts anybody else. All conversation is obfuscation. And if you open your ears, you hear a rising murmur of discontent among the people the institution is supposed to be serving.

Does that sound like your office? Then how about your country? The creepy workplace portrayed in Harold Pinter’s political-Gothic comedy “The Hothouse,” which opened last week in a revival at the National Theater, has a familiarity that draws hard but anxious laughter from London theatergoers, the kind that erupts when the lines between funny and scary blur.

While audience members may be laughing together at “The Hothouse,” which finds the malevolence in the brusque comic rhythms of the music hall, they’re unlikely to experience that communal warmth that usually comes from people responding at the same time in the same way. “The Hothouse,” like most of Mr. Pinter’s work, leaves you feeling suspicious — of language, social rituals and, above all, other people.

Such mistrust fits the mood in London, where newly exhumed scandals involving the Blair cabinet and the BBC have temporarily dislodged Russian assassins and the threat of terrorism from the front pages. (A typical headline, from The Guardian, reads, “Can You Believe Anything You See on Television?”)

Even the season’s big publishing event, the latest Harry Potter novel, is centered on a children’s book about the loneliness of not knowing whom to trust. “Only connect,” E. M. Forster’s hopeful invocation in the 1910 novel “Howards End,” doesn’t really cut it these days as a motto.

Fortunately, this negative sensibility can generate a crackling positive charge in drama. Witness the electricity in two strong works from different eras that find weight and tension in the idea that you can’t go home again: “In Celebration,” David Storey’s 1969 anatomy of upward mobility in an English coal-mining town, and “Baghdad Wedding,” an auspicious debut drama by Hassan Abdulrazzak about love among the ruins of contemporary Iraq.

But it is Mr. Pinter, who won the Nobel Prize in Literature two years ago, who forged the template for the modern drama of disconnection. And at 76, he is once again the playwright of the moment.

In addition to “The Hothouse,” which Mr. Pinter set aside for more than 20 years after writing it in 1958, the Donmar Warehouse recently staged a transfixing revival of his “Betrayal,” the drama of marital infidelity that opened to contemptuous reviews here in 1978. If “The Hothouse” doesn’t quite emerge as a masterpiece for the ages, “Betrayal,” which sadly ended its limited run on Saturday, definitely does.

As he did with his compelling revival of Mr. Pinter’s “Old Times” (also at the Donmar), the director Roger Michell brings a cutting emotional urgency to a study in the unbridgeable distances that exist within the intimacy of love, marriage and friendship. The up-close-and-personal Donmar, where listening feels like eavesdropping, is ideal for this kind of dissection.

As is essential to any good “Betrayal,” which is told in reverse chronology, Mr. Michell’s staging provided a careful map of the shifts in alliance and power among Emma (Dervla Kirwan); Robert, her husband (Samuel West); and Jerry (Toby Stephens), her longtime lover and Robert’s best friend. What emerged with unusual vividness was the pang of solitariness in these characters, even in the closest quarters.

The macho loucheness of Mr. Stephens’s Jerry never disguised a needling, pose-thwarting insecurity. Mr. West’s very fine, ferociously passive-aggressive Robert laid bare the emptiness in the satisfaction of having the upper hand, while Ms. Kirwan located a pained, self-defeating longing for an idea of home that Emma could never hope to achieve. Banal phrases (“How are you?,” “Read any good books lately?”) acquired the urgency of distress signals.

By comparison with the compact “Betrayal” (90 fluid minutes), the two-and-a-half-hour “Hothouse” sprawls. Mr. Pinter has said that he did little to revise this early effort, which portrays double dealings in a contemporary mental hospital, when he decided to stage it (under his own direction) in 1980, and it’s one of his few works that need editing.

Ian Rickson’s disquieting production, the first “Hothouse” at the National, occasionally goes slack through repetition that turns social metaphor into bald allegory. And I’m not sure that any play from a master of claustrophobia benefits from the wide-open spaces of the Lyttelton stage.

But the look and sound of the production beautifully summon both institutional sterility and the threat of things unspeakable in the shadows. And the performances, particularly from Stephen Moore as the rattled megalomaniac in charge and Finbar Lynch as his ice-blooded lieutenant, pricelessly illuminate the brutality in slapstick and the Abbott and Costello-style absurdity in circular bureaucratic lingo. Before “Beyond the Fringe” and Monty Python, there was Harold Pinter.

If Mr. Pinter’s dialogue hinges on that which is unsaid (or can’t be said), that of the novelist and playwright David Storey eagerly spells things out. “In Celebration,” which opened last week at the Duke of York’s Theater, is a hyperarticulate examination of parental expectations gone wrong. The story of a family reunion in a dying coal-mining town, it is, like much British literature, about class and especially about what gets lost in climbing the economic ladder.

“We are the inheritors of nothing,” says Andrew Shaw (Paul Hilton), one of three surviving sons of a miner (Tim Healy) and his wife (Dearbhla Molloy), who devoted their lives to pushing their children into the bourgeoisie. The hostile Andrew is the speechifier in the family, and he may talk too much for the play’s good. (The movie actor Orlando Bloom, in a creditable stage debut, plays the silent son and accounts for the unlikely presence of American teenage girls in the audience.)

But there’s energy in the invective throughout, as well as exquisite renderings by Mr. Healy and Ms. Molloy of the surprised pain beneath their characters’ stoicism. Ms. Molloy’s silent scream in the last scene might be an emblem for all parents and grown children who realize what a wide gulf now separates them.

The blame-the-parents gambit doesn’t cover the alienation felt by the characters in “Baghdad Wedding,” which ended its run at the Soho Theater last week. This first play by the Iraqi-born Mr. Abdulrazzak revolves around a disastrous wedding that takes place on the eve of the 2005 elections in Iraq, where cultural identity is mutable and life is tenuous.

Directed by Lisa Goldman, “Baghdad Wedding,” which traces the fortunes of British-schooled Iraqis who return to their native land, has some of the appeal (and conventionality) of popular love stories set in countries in upheaval (“Gone With the Wind,” “Dr. Zhivago”). And its charismatic, quicksilver hero, a bisexual novelist named Salim (Matt Rawle), is in the precast mold of fictional fascinators like Jay Gatsby and Sebastian Flyte (of “Brideshead Revisited”).

But Mr. Abdulrazzak packs an affecting and frightening sense of anomie within this framework. Ordinary people, a description that embraces both Iraqi insurgents and American soldiers, are transformed into monsters. (Like “The Hothouse,” “Baghdad Wedding” features harsh scenes of torture.) And many of the play’s central characters, who memorably include a vivacious and free-living London medical student (the charming Sirine Saba), are altered to the point where they barely recognize themselves, let alone one another.

“Am I the outsider or the insider?” asks Salim.” As in Mr. Pinter’s world, the answer keeps changing.