Criss, 24, has rehearsed intensely while on a break from the hit Fox TV series.

That practice showed in his opening night perfromance, which was as slick and shiny as his Brylcreemed hair.

Making his entrance suspended on a window washer’s hoist, he was greeted by raucous cheers from a capacity crowd at the Al Hirschfeld Theatre.

The audience, 1,400-strong, was crammed with “Gleeks” of all ages plus devoted fans of Criss’s YouTube “Harry Potter” parody, “A Very Potter Musical.”

Read the full story on nydailynews.com