Much of what happens in 'The Lehman Trilogy' is invisible to the eye, which is not the way prestige drama usually works onstage. Directed by Sam Mendes, this British import, which reaches across 164 years of American history to trace the family saga behind the fallen powerhouse Lehman Brothers, was a scalding-hot ticket during a brief prepandemic run at the Park Avenue Armory. Yet it offers almost nothing in the way of spectacle, and only the slightest of costume changes: a top hat here, a pair of glasses there. In the captivating production that opened on Thursday night at the Nederlander Theater, it relies largely on an unspoken agreement between actors and audience - to imagine together, and let fancy crowd out fact.