Two things about Eric Schaeffer’s Twentieth Century seem just impossibly sleek: James Kronzer’s fabulous streamliner of a set, which sends the title’s ’30s-vintage luxury train gliding glamorously across the Signature Theatre stage, and James Barbour’s fast-talking, wheeler-dealing theatrical impresario, a preening egomaniac who’s never met a moment he couldn’t milk. Would that all of the show’s elements exhibited as much style.

Barbour is a tallish fellow, to be sure, but his height isn’t what makes his character seem so much bigger than the mere mortals who board the swank Chicago-to-New York express with him. This is a performance that’s all about performance, an unabashed ham-it-up with a thick glaze of professional polish, a theater veteran’s expertly outsize depiction of a theater veteran and the blatantly theatrical affectations that make him as infuriating as he is irresistible. It stops just this side of over the top, and scene after scene, it’s the feeling that Barbour might be headed for a spectacular derailment that makes the ride such a rollicking one.

Audiences will fall for Barbour’s Oscar Jaffe a good deal earlier than Holly Twyford’s Lily Garland does, but then she’s got to hold out: It’s Jaffe’s outrageous schemes to lure her back into his arms—and onto his stage—that drive Twentieth Century’s slight but sexy plot. Bankrupted by a string of Broadway bombs, threatened by an upstart producer who learned the trade at his very knee, Jaffe is prepared to pitch woo, lie through his teeth, sacrifice a subordinate or two, fake a death, and play both ends of a smoke-and-mirrors business deal against the middle to get Lily’s name on the contract that will stave off his creditors and keep his personal marquee in lights—all of which, and more, he merrily does before Ben Hecht and Charles MacArthur’s madcap farce pulls into Penn Station.

Hecht and MacArthur were the writers behind The Front Page and its peerless film incarnation, His Girl Friday, and Ken Ludwig (Lend Me a Tenor, Moon Over Buffalo) has updated and adapted the script, so unlikely coincidence is a given in Twentieth Century. With these gentlemen pulling the strings, it’s inevitable that a producer in need will find himself on a train with an aspiring playwright (Thomas Adrian Simpson’s stagestruck surgeon, Grover Lockwood), an ancient Passion-play actor from Oberammergau (Rick Hammerly, in one of several small parts that would be scene-stealer sinecures if everyone else hadn’t sunk teeth so firmly into the sets), and a pharmaceutical heiress (Donna Migliaccio) whose religious inclinations make her the perfect angel for a desperate impresario whose last flop centered on Joan of Arc. And it’s inevitable that at least one of those three—at the least opportune moment for poor Jaffe—will turn out to be a raving nut job.

Anne Kennedy’s costumes, fluent in the language of ’30s fashion even if they’re not actually vintage, are every bit as much mad fun as that addled character, and aside from a few moments of sluggishness in the first act, director Schaeffer keeps the proceedings clicking along. Most of his cast members have mastered the sharp comic timing essential for such brittle farce, too: Migliaccio is a twitchy, canny hoot as Myrtle Clark, and Twyford, particularly, matches Barbour mug for mug in their scenes together, capping her portrait of a stage diva gone Hollywood with a triumphantly awful bit of overacting when Jaffe’s rival (the indispensable Hammerly again) offers her a juicy new part.

The soft spots include Will Gartshore, who often leans too hard on the malapropisms the script hands him; he’s the earnest young idiot of a lover who boards the train with the hard-as-nails Lily, and Ludwig et al. have given him regular opportunities to suspect that his inamorata is planning to “get amorphous” with someone else, and so on. He hits nearly as often as he misses, but it would all be a good deal crisper if he (and Schaeffer) would demonstrate a willingness to move on before the line has landed. Harry A. Winter, otherwise solid as Jaffe’s long-suffering, level-headed deputy, is another exception, especially early on; his unaccountably slow-off-the-mark reactions to Jaffe’s outrageousness kill more than one laugh.

Then, too, there’s fault to be found with the script; whether it’s Ludwig’s updates or the original text, there are a few head-scratchers laced in among the sharper lines. More than once, a character steps away from the play’s urbane-comedy baseline to deliver a one-liner rooted in vulgar double-entendre. (“By day I may be a surgeon,” says that playwright manqué, “but at night, alone in my bedroom, using nothing but a simple pen, I explore my inner reaches.”) It’s not offensive or even off-putting, exactly—just off-kilter, given the evening’s general tone.

All these little oddnesses add up to a comedy that never quite becomes a riot. Hilarity most certainly ensues when Twentieth Century pulls out of the Signature station, but only intermittently, and never transportingly. It’s a ride worth taking, to be sure, but it’s not exactly a trip. CP