Who is Angela Lansbury to you — Jessica Fletcher? Mame? Mrs. Lovett? Mrs. Potts?

The 89-year-old wonder is playing Madame Arcati in Noël Coward’s chestnut “Blithe Spirit,” and if a supporting performer were ever reason enough to see a show, this is it. As the whimsical medium who accidentally conjures up a writer’s dead wife (much to the displeasure of his current spouse), the creamy smooth Lansbury coos and twitches, moves across the National Theatre stage like an anxious bird trying to walk like an Egyptian, and makes every exit a delight. Arcati is a famously scene-stealing role, but one that performers often huff and puff through to make funny. Lansbury simply pops the cork and sparkles.

It’s a Tony-winning performance: Lansbury won in 2009 (her fifth triumph) and has since reappeared in Michael Blakemore’s assured production in London and in this four-city North American tour. These two weeks at the National mark the end of the line, and for theater buffs it’s an event.

It takes a star of Lansbury’s magnitude to make it so, but the history she carries with her packs the National and gives the evening a kind of throwback energy. Nostalgia? Partly, and it’s well-earned: Her spectacular career stretches back to 1944 and the film “Gaslight.” But Lansbury has always been an intuitive and conscientious performer, and in “Blithe Spirit” she is utterly on point. She inventively gets inside the character, playing Arcati with cutting looks and dry replies lobbed at the sophisticates who cynically think she’s a dotty fraud.

The play itself isn’t the greatest Coward; in April 1941 he wrote it in a week, and the “improbable farce,” as he called it, was entertaining a war-torn London by July. But as writer Charles Condomine (Charles Edwards) finds himself caught between two wives, the lighthearted ghost comedy manages to touch on Coward’s long-standing concerns about the tensions between love, lust and independence.

Angela Lansbury as Madame Arcati in the North American tour of Noël Coward’s BLITHE SPIRIT. (Joan Marcus)

Blakemore’s bright production even opens with the breezy flair of Coward’s immortal romantic smashup “Private Lives,” as Edwards — best known here as Lady Edith’s doomed publisher lover on “Downton Abbey” — banters elegantly over martinis with Charlotte Parry’s Ruth (the smart but prickly second wife). As designed by Simon Higlett, the Condomines’ house in Kent is chic and airy, and Higlett’s costumes give the couple an English savoir faire that matches Coward’s highbrow barbs. (Arcati’s tastefully eccentric costumes are by Martin Pakledinaz in tones that perfectly match Lansbury’s curly auburn wig.)

The story’s machinery is triggered when Charles invites Arcati to lead a seance as research for his next book. But to set the mood, Arcati puts the sentimental “Always” on the phonograph, and oh, dear — in blows Elvira, Charles’s giggly, mischievous, sensual first wife who died seven years ago.

The shtick isn’t foolproof as the vise of competing wives tightens on Charles, but Blakemore’s cast keeps its footing even as Coward belabors his joke. Edwards is a debonair Charles, Parry makes a sharp-witted and quick-tempered Ruth, and as the spectral Elvira, Melissa Woodbridge merrily sails around in a gauzy white nightgown, her smile made wicked and temptingly alive by a slash of red lipstick.

Confidence keeps the enterprise afloat, and there is just enough comic surprise to keep it bobbing decently even as you begin to sense Coward’s hand cranking at the motor. Unexpected syncopations in timing and stage business ensure that the laughs never dry up, with Susan Louise O’Connor supplying a particularly memorable sight gag as the Condomines’ high-strung housekeeper.

But talk about an ace in the hole: Without ruffling a feather, Lansbury commands things every time she appears. The role takes substantial energy, and you marvel at how she summons it — and how, when an actor comes through as Lansbury does, it lifts everyone. That’s the mystical power of this kind of performance: we can all have what she’s having.

Blithe Spirit

by Noël Coward. Directed by Michael Blakemore; lights, Mark Jonathan; sound, Ben and Max Ringham. With Simon Jones and Sandra Shipley. About 2 hours and 40 minutes. Through March 29 at the National Theatre, 1321 Pennsylvania Ave. NW. Tickets $48-$228. Call 800-514-3849 or visit www.thenationaldc.com.