LONDON, June 21 — Now what was that old nonsense about Tom Stoppard as all head and no heart? Mr. Stoppard’s exciting new play of immutable passions and mutable politics, “Rock ‘n’ Roll,” which opened last week at the Royal Court Theater here and has become the hottest ticket in town, is so flush with feeling that it never seems to stop trembling.

Of course any show that makes extensive use of the amped-up anthems of vintage Pink Floyd can hardly help vibrating. Yet songs are never just audience-revving mood music in this production, directed with lightning crackle and flash by Trevor Nunn. In recordings by Pink Floyd, the Velvet Underground, the Grateful Dead and (but of course) the Rolling Stones, among others, Mr. Stoppard locates the very rhythm of life, a pulse that remains steady if sometimes faint through the vagaries of the histories of nations and governments. “It’s only rock ‘n’ roll,” a phrase quoted inevitably and to devastating effect, is here the most monumental of understatements.

Set largely during the years of the Soviet occupation and control of Czechoslovakia, where the British-educated Mr. Stoppard was born, “Rock ‘n’ Roll” follows the entwined fortunes of Max (Brian Cox), a Cambridge professor and devout member of the Communist Party, and his student disciple, Jan (Rufus Sewell), a Czechoslovak who leaves Cambridge for Prague in 1968 in response to the arrival of Soviet tanks. (The play is dedicated to Vaclav Havel. He attended the opening night, along with Mick Jagger, who also figures as an unseen but influential character in “Rock ‘n’ Roll,” which transfers to the West End next month.)

The ideological differences between Max and his former pupil — as well as among Jan and his Czechoslovak contemporaries, and Max and practically everyone who crosses his line of vision — offer ample occasion for winged considerations of politics, ethics, semantics, biology, mythology, philology, classical literature (Max’s wife, Eleanor, played by Sinead Cusack, teaches Greek) and, well, you name it. This is a Stoppard play.

Even more than his intimate, introspective “Real Thing,” “Rock ‘n’ Roll” presents all theory as secondary to a distinctly noncerebral spirit. An equally word-driven playwright, George Bernard Shaw, called it the Life Force. Mr. Stoppard calls it Pan: “a beautiful boy as old as music, half-goat, half-god.” The Pan-ic spirit defies, subverts and survives all social orders. This is just as well, as “Rock ‘n’ Roll” proposes that falling in love with any political ideal is a guaranteed recipe for heartbreak.

Part of the Royal Court’s 50th anniversary celebration of the founding of the English Stage Company, which produced John Osborne’s era-defining, iconoclastic “Look Back in Anger” in 1956, “Rock ‘n’ Roll” is not obvious Royal Court fare. The high-brow chic associated with Mr. Stoppard seems at odds with the grittier, more confrontational work that became the Royal Court’s signature.

But despite typically ornate erudition, this latest offering from the author of “Rosencrantz & Guildenstern Are Dead” and “The Invention of Love” could hardly be more appropriate to the disenchanted and perversely nostalgic mood that seems to possess Britain at the moment. The same week that “Rock ‘n’ Roll” opened, much affectionate attention was given to a Who performance at the University of Leeds, a homage to the group’s fabled 1970 concert there. The latest sitcom from the sardonic Steve Coogan offers a surprisingly warm portrait of a beer-bellied exterminator who remembers glory days as a rock roadie in the 70’s.

At the same time the rancorous satires and protest plays that sprouted in the shadow of the invasion of Iraq have given way to more detached, skeptical works that question the satisfactoriness of any political system. In the current repertory at the National Theater are both Mike Leigh’s “Two Thousand Years,” the tale of a leftist Jewish family that has drifted from spirited engagement to fretful resignation, and David Eldridge’s “Market Boy,” a sprawling pageant of a play that chronicles the rise and fall of Thatcherism, with little hope expressed for the years to follow.

“What is to be done?,” as Max asks, in self-mocking quotation marks, in “Rock ‘n’ Roll.” That was the title of Lenin’s famous turn-of-the-last-century pamphlet, and it rumbled throughout Mr. Stoppard’s last previous full-length (very full-length) work, “The Coast of Utopia,” his trilogy about Russian intellectuals on the cusp of revolution, first staged at the National Theater four years ago and to be produced by Lincoln Center Theater later this season. “What is to be done?” might also be the mantra of “Enemies,” a new adaptation by the industrious David Hare of Maxim Gorky’s 1906 drama of aristocrats and proletariats at loggerheads, which ends this weekend at the Almeida Theater.

Performed with naturalistic vibrancy by a fine cast directed by Michael Attenborough, “Enemies” oozes the juicy ruling-class angst, idiosyncrasy and moral paralysis associated with classic Russian fiction. But it also presents an array of ardent, revolution-ready factory workers. The more insightful of the fluttery aristocrats envy the workers their certainty. But it’s telling that the uncertainty of the doomed upper-class characters is what feels convincing, and unsettlingly familiar.

Certainty demands a contorting leap of faith in “Rock ‘n’ Roll.” Played by Mr. Cox with the hair-trigger irascibility of a man who has spent his adult life on the intellectual and moral defensive, Max is a British academic who was born on the day of the October Revolution and remained faithful to its tenets through the years of Stalin and beyond.

For Jan, whose evolution is rendered in ravishingly authentic detail by Mr. Sewell, religion is music. “I came back to save rock ‘n’ roll,” he says of his return to Prague in 1968, adding after a pause, “and my mother, actually.” His association with an underground Czech rock group, the Plastic People of the Universe, leads to his imprisonment as a dissident.

Both men’s beliefs are challenged and tempered by events historical and personal in a succession of quick scenes, punctuated by snatches of period songs. Debates, replete with eminently quotable phrases and labyrinthine twists, flicker and flare.

Some critics have written that Mr. Stoppard is pursuing too many thematic strands here. But for me every element of plot and character — from Eleanor’s Greek tutorials to the intergenerational fascination with Pink Floyd’s Pan-in-residence, Syd Barrett — ultimately feeds the notion of an élan vital that cannot be quantified or reduced to academic or anatomical equations.

In a scene played with unforgettable ferocity by Ms. Cusack (who also portrays Eleanor’s grown daughter in the second act), Eleanor, dying of cancer, condemns Max’s mechanistic views: “I am not my body; my body is nothing without me.”

Acknowledging the triumph of a spiritual essence that cannot be captured in words may seem odd coming from Mr. Stoppard, whose career has been predicated on the search for the mot juste. But at 68, he appears to have succumbed to the sentimentalist within. His dazzling whirligig of a mind may be in full spin here, but he is definitely leading with his heart.

If this orientation dictates, in the second act, the sort of romantic contrivances that only Shakespeare gets away with, so be it. This is Mr. Stoppard’s most emotionally generous play. His characters must take a rough and depleting journey. They deserve their happy endings, however provisional. And of course whatever music makes them happy.