Agneta Stjernlöf-Valcu and Victor Valcu have been traveling the world since they retired as ballet masters — but not as tourists.

Instead, the two stagers have been helping set “Onegin,” a ballet based on Alexander Pushkin’s poem, for companies worldwide — most recently, Boston Ballet.

“Onegin,” choreographed by John Cranko in 1965 for the Stuttgart Ballet, is a tragic love story that puts on display the culture and social dynamics of nineteenth-century Russia. Onegin, a snobbish aristocrat, rejects Tatiana’s love only to regret it several years later.

It's the stager's job to ensure that the choreography and style of the production stays true to the original. Valcu was one of the first people to dance the role of Onegin in 1976. His wife, Stjernlöf-Valcu, is a choreologist – someone who notates the choreography so that it can be preserved and passed on – for about 120 ballets, and has the original notations for “Onegin.”

"I’m the policeman,” Stjernlöf-Valcu says. “I make sure that everyone does the steps correctly, does the choreography correctly.”

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The Stuttgart Ballet holds the rights to “Onegin,” and only permits certain people to stage it – Stjernlöf-Valcu and Valcu are two of only five people worldwide who are able to stage the ballet.

Not any company can perform the ballet, either. The Stuttgart Ballet has to believe that the ballet company is strong enough to do the production justice. The stagers explained that this is because of the ballet’s technical difficulty and the depth of acting that’s required.

“We very often have Tatiana, at the end, just crying – for real,” Stjernlöf-Valcu says. “It’s such strong emotions in this ballet.”

“It demands knowledge, talent [and] experience,” Valcu says. “And good teaching, and we are good teachers – I joke, I joke.”

Valcu and Stjernlöf-Valcu explain that they keep staging the production because there continues to be companies that want to dance it. They know it'd be fun to stage a new production, but they keep coming back to “Onegin.”

“It’s a ballet you don’t get sick of,” Stjernlöf-Valcu says.

Boston Ballet will perform “Onegin” from Feb. 25 to March 6 at the Boston Opera House. Tickets start at $35 at BostonBallet.org.