Episode nine of Entrances, Exits, & Everything in Between, an online documentary of Broadway diva Patti LuPone being created (literally) on the run by her son, Josh Johnston, shows what happened behind the scene of LuPone's recent appearance on the weekly #Ham4Ham concert series on the steps of the Richard Rodgers Theatre, where Hamilton is playing.

In the clip, we see LuPone and Hamilton creator/star Lin-Manuel Miranda meeting on West 45th Street, slipping incognito through the crowds waiting for digital lottery tickets to the show, going backstage at the Rodgers, walking across the stage (with Miranda singing a snatch of one of her songs from the 1976 musical Working), sharing war stories, trying to decide whether she should go “full Merman” in her performance, then bursting out onto 46th Street so she can belt George M. Cohan's “Give My Regards to Broadway.”

Watch the entire episode here: