Even the smog of Istanbul has a sort of exotic charm, according to one of the characters in “Pera Palas.” A wonderfully jumbled look at a century or so of Western experiences in Turkey, the new Long Wharf show takes its title from a hotel built for Western travelers on the Orient Express.

The script unfolds in three periods of the 20th century: the decade following World War I, the early 1950s, and the mid-1990s. Linking the three periods is a sometimes difficult-to-follow lattice of interlocking, mainly twice-cast characters. The stories run concurrently and often simultaneously on the stage, and the dialogue from each mingles to form a remarkably coherent narrative.

According to the program notes, Turkish-American playwright Sinan Unel wrote the play partly to educate his American audience about Turkey. Much of the weight of this political, historical message is borne by the the earliest segment. The protagonist of this portion, Evelyn Crawley (Christina E. Rouner ’84), a feminist journalist alarmed by the world of the Turkish sultanate, is a delicately calibrated mix of colonialist and tourist.

“You’re being kept prisoner in a gilded cage,” Evelyn informs her young Turkish protegee Melek (Andrea Gabriel), who wants only to marry and have beautiful children. Her attempts to change Melek’s fate are well-intentioned but condescending, and they lead to sadly unforeseen consequences.

In the second section, a young American named Kathy (Kathleen Early), falls in love with a charming Turkish man, Orhan, (Brandon Demery) who promises to free her from her conventional Midwestern family. In the third storyline, Kathy (now Glynnis Bell) and Orhan (now Jonathan Hadary) are all grown up and alienated from their two children Murat and Sema. Murat (Paul Anthony Stewart) has reversed his mother’s path by leaving Turkey for America, and high-powered lawyer Sema (Rouner) has a secret romantic life.

Unbeknownst to his family, Murat has returned to Turkey for a brief visit, accompanied by his lover Brian (Jeremy Webb). The scenes between Murat and Brian are the most lighthearted of the play. Although Murat’s family has serious problems, “culture shock” for the couple primarily consists of Brian’s terrible reaction to Turkish food. Delightfully silly rather than cheap, the constant stream of jokes is a much-needed relief from the struggles of the other characters. It’s not incidental that Webb has the honor of making the only Canada joke in the show.

The success of this complex ensemble show is largely dependent on its creative, unpredictable casting. In one great transition, the character of Bedia grows from a slight and submissive concubine (Early) to a hulking matron (Jonathan Hadary again, and yes, that’s correct) who is thrown into despair upon hearing that her future daughter-in-law, Kathy, is from Ohio.

“My son is marrying a peasant!” she complains.

More conventionally, the double-casting of Demery and Hadary as Orhan, an elegant young husband in the 1950’s and a bombastic, drunken father in the 1990’s, is effective. The two actors seem to occupy the same emotional space, even as they confront one another across the stage and time. Hadary’s, in particular, is a virtuoso performance, and seeing it reflected so painstakingly in Demery makes it all the more impressive.

Unfortunately, elsewhere the casting is downright baffling. Cavid, a progressive young Turk of the 1920’s (Webb again) reappears in the 1950’s as a sort of family friend, but Glynnis Bell’s Cavid is such a quantum leap away from the earlier version that the character is difficult to place. In addition, either Cavid’s later scenes have little purpose as scripted, or Bell is simply not getting the message across.

This is one example of a few moments where both Unel and director Steven Williford seem to be carried away by their own cleverness into unnecessary elaboration. Confusing and unnecessary characters and tedious narration, often spoken by Rouner’s Evelyn Crawley, make the show drag in places.

The breadth of the script and multitude of its characters allows it to grapple with familiar themes of culture clash and personal transformation in many different contexts.

“Fish in America don’t glare,” Brian deadpans to Murat, explaining his reluctance to sample Turkish delicacies. That’s a joke, but when the newly affianced Orhan attempts to reassure his mother about Kathy by saying “She’s a nice girl — she’ll respect and obey,” it’s clear that more deep-seated cultural differences are at work. In a paired theme, Unel treats nicely his character’s definitions of freedom, as they fight over both what it is and where it can be found.

Despite its occasional excesses, this ingeniously constructed and well-acted show is worth the effort of puzzling it out.