Long after most people have switched to decaf for the night, there's a party underway fueled by adrenaline and espresso.
Inside a narrow and noisy Pilcrow Cofee, some of the area's top baristas have come together for a competition called a latte art throwdown.
As Colectivo Coffee barista Sean Loo explained, the challenge is drawn in foam.
"A throwdown is just a bunch of people coming together, pouring milk on top of espresso," Loo said.
On this late January night, 32 baristas from across Milwaukee and the suburbs have thrown $5 into the pot and put their names into a March Madness-style bracket.
Two by two, they face off. Each barista pours their best example of latte art, judged by three of their peers.
Most days, Martha Blanchard is a Colectivo barista. On this night, she is judging the work of those hoping to take home the pot and bragging rights.
As she explained, judges want to see good contrast between the white of the foam and the dark of the espresso. The art needs to be symmetrical, centered in the cup. It also needs to have the detail of a well-poured piece of art.
Onward it goes, two at a time, until the bracket collapses to the last barista standing.
This night, it was Andrew Pip from Kickapoo Coffee in the Third Ward.
While it was not quite the same as winning a gold medal, Pipp still had pulled off a feat worth celebrating.