ROMANCE, INTRIGUE AND ABSURDITY: Evan Thompson as the dashing Richard Hannay and Holly Linneman, who plays all three of Hannay’s love interests, strike a pose in rehearsal for Princeton Summer Theater’s production of “The 39 Steps,” playing at the Hamilton Murray Theater on the Princeton University campus through July 28.

In the opening moments of Princeton Summer Theater’s ceaselessly entertaining The 39 Steps, Richard Hannay, the dashing hero, sits alone in his London apartment. It’s 1935, between the Wars. He is sipping his scotch and soda and suffering the pangs of ennui.

“Picked up an evening paper, put it back. Full of elections and wars and rumors of wars. And I thought — who the bloody hell cares frankly? What does it all matter? What happens to anyone? What happens to me? No-one’d miss me ….” He then decides, “Find something to do, you bloody fool! Something mindless and trivial. Something utterly pointless. Something — I know! A visit to the theater! That should do the trick!” And his action-packed adventures commence.

True to its iconic source material, which it both spoofs and celebrates, The 39 Steps, adapted by Patrick Barlow from a 1915 detective novel by John Buchan, a 1935 Alfred Hitchcock movie, and an original concept by Simon Corbel and Nobby Dimon, is a murder mystery thriller. There’s the suave protagonist; exotic, beautiful, and mysterious heroines; unremitting intrigue; a desperate struggle, with the fate of England at stake; narrow escapes; train chases; airplane crashes; treacherous bridges; a dastardly Nazi villain with a missing little finger; and much more.

But this 2005 British hit, still running in the West End, brought to the U.S. in 2008 for a Roundabout Theater production then two years on Broadway, goes far beyond its source material. With minimal set and only four actors playing all — I lost count at 130 — parts here, The 39 Steps becomes a tour de force that revels in the magic of theater and the amazing, inventive, ridiculously implausible act of creating something out of only the performers’ creative imagination and the audience’s willing suspension of disbelief.

“Mindless and trivial”? “Utterly pointless,” as Hannay says before heading off to the theater? Yes, indeed, particularly in this rambunctious, outrageous, and whimsical mode — but hard to beat for sheer fun and theatrical virtuosity.

This parody of Hitchcock’s famous movie, with additional allusions to Stranger on a Train, Rear Window, Psycho, Vertigo, and North by Northwest, will resonate with film buffs, but no prior film knowledge is necessary to enjoy this show, which is much more about theatricality than film. In its rapturous embracing of the challenges of staging the unstageable, in its wildly energetic and ridiculously serious commitment to creating the plentiful characters and the murder mystery/spy thriller world of the play, the four actors and their top-flight production team deliver a delightfully engaging and thoroughly entertaining evening.

Jeff Kuperman, busily involved in New York theater, dance, and film over the past year since his Princeton University graduation, has directed and choreographed The 39 Steps with fabulous timing and an unerring comic sense. The melodrama, the high camp, the breakneck pace, the coordination of props, actors, sound, lights, costume changes, and the unremitting physical and verbal humor could easily misfire in the hands of less skilled, committed and talented performers, and production crew. The professional Princeton Summer Theater team is highly focused and carefully, skillfully rehearsed — even more impressive here than in their two fine productions (the intimate musical comedy She Loves Me and the comedic southern gothic Crimes of the Heart) earlier this summer.

After Hannay’s brief opening scene, the plot wastes no time in picking up speed. At the theater Hannay (Evan Thompson) meets a beautiful, mysterious woman (Holly Linneman), who turns out to be a foreign spy. When, in the middle of the night, she lands in his lap with a knife in her back and a map of Scotland in her hand, Hannay quickly realizes he must find the ruthless perpetrators, a clandestine organization called “the 39 Steps.” He also must escape both the authorities who suspect him for murder and the villains who want him dead, and solve this international espionage mystery before vital security information leaves England. The chase is on!

As the debonair hero, Mr. Thompson adopts the perfect balance of camp and commitment, of ironic detachment, and deadly serious involvement in his heroic and romantic quest. He plays almost every spy thriller cliché you can imagine with appropriate panache that is larger than life but never overdone. The age stretch is daunting — Mr. Thompson is a couple of decades away from the age 40ish world weariness of the character as originally conceived, but he blends the Hitchcock and Monty Python styles brilliantly to provide a solid core to the production.

Ms. Linneman, with an eccentric array of wigs and accents, plays all three leading ladies — all stunningly beautiful, all intricately involved in the fate of Hannay, and all straight out of the conventions of the film noir spy thriller tradition. As ill-fated foreign spy, then innocent, amorous, doe-eyed country lass, then savvy woman of the world, she is a worthy counterpart to Hannay. She keeps up her defenses, sparring verbally and physically with Hannay until the end. Ms. Linneman is on target, thoroughly in character — all three characters — while playing the high drama and romance just broadly enough to suit the prevailing tone of spoof and hijinks.

And the other 130 plus roles fall into the capable hands — and legs and faces and every other conceivable body part and vocal distortion and costume piece — of Brad Wilson and Pat Rounds, listed in the program as simply Clowns 1 and 2. These astonishingly versatile performers, who act, sing, dance, and perform all sorts of physical and vocal acrobatics throughout the evening, do not need named-in-the-program leading-character roles in order to steal the show.

Perhaps the greatest delight of watching The 39 Steps comes in observing the imagination and virtuosity of these zany, chameleon-like actors as they instantaneously transform themselves and their settings into whatever this plot-laden script demands. My favorite hilarious transformations include Mr. Wilson’s jealous old crofter husband; all of his outrageous, bewigged, heavily accented gender crosses — the shocked maid, the domineering wife of the villain and the Scottish innkeeper’s wife; Mr. Rounds’ dastardly, pinky-less spy master and heavy-handed Scottish innkeeper; the two clowns’ dazzling simultaneous depictions of train passengers, porter, paperboy, conductor, and policeman; and, of course — quite a character stretch even for these theater magicians, the roles of puddles in the road on the dangerous journey through the Scottish moors. Individually, in tandem and in interactions with the two protagonists, Mr. Wilson and Mr. Rounds provide the audience with an abundance of laughs and surprises.

The production elements here are almost as remarkable as the fine performances. Jeffrey Van Velsor’s minimal set — ladders, chairs, wheeling doors and windows — affords unlimited possibilities and opportunities for this company to display its ingenuity and boundless imagination. (What they do with windows must be seen to be believed.) Laura Hildebrand’s technical direction and Alex Mannix’s lighting design, along with sound design by Mr. Kuperman, all cohere to create this wild romp through a caricatured world of murder mystery and romance. The comic timing—actors’ delivery of lines, gesture, interactions, and physical humor, sound, lighting, props and set movements — is consistently on point.

In the same Monty Python-esque, larger-than-life mode, Annika Bennett and Maeve Brady’s richly inventive, colorful costuming — featuring a wild collection of wigs, hats, and numerous other accessories, and Gordon Jacoby’s dialect coaching skillfully both create and mock the world of The 39 Steps.

Don’t look for interesting character psychology, depth, or development here. Despite the distinguished source material, don’t look for a plausible or even consistently comprehensible plot to keep you on the edge of your seat. But “a visit to the theater” certainly helped Richard Hannay to overcome his ennui, and for sheer entertainment, hilarity, and a joyful tribute to the wonders of theatricality, PST’s production of The 39 Steps is bound to please.