When we heard that Jay-Z would be live-streaming the final concert of his eight-night stint at the Barclays Center, we allowed ourselves the tentative hope that Hova would close out the series with a special guest of some kind—Santigold, maybe? As it turns out, we were dreaming too small. When Jay did in fact bring out a surprise guest, it was one of the biggest stars in the world, and also his wife.

Beyonce joined Jay onstage for a brief performance last night, and for five minutes the Barclays Center was transformed into a full-blown Beyonce concert. (She even brought her own backup dancers!) Dressed in her own custom Brooklyn Nets apparel—gotta represent the brand at all times—Bey entered through a cloud of dust to perform Sasha Fierce deep cut "Diva," before launching into a rousing performance of "Crazy in Love." Even Jay was spellbound: When it came time for his verse he was nowhere to be seen. Presumably he was as lost in the spectacle as everyone else.

Afterward, Jay seemed elated by his wife's surprise appearance. "Of course I had to let BK touch the stage in BK," he told the crowd.

That wasn't the end of it, though. For the concert's finale, Jay brought Bey out for an encore, as she took on the Mr. Hudson/Alphaville part on "Young Forever."

We could see this slower version of the Blueprint III track becoming their version of a Carter/Cash classic, the standard they trot out when they're still touring arenas in their '60. And if that image seems a little too rosy of an image for you, well, it suits the vibe of these Barclays nights, a weeklong festival of nostalgia and good feelings that ended with a vision of marital love even Rick Santorum would have enjoyed.