The song Jeffrey sings when greeting Beatrix is "Hello, Little Girl" by Stephen Sondheim from the Broadway musical 'Into the Woods.'
This episode is full of references and tributes to the musicals of Stephen Sondheim (1930-2021). Jeffrey (Richard Kind) greets Beatrix (Rhea Perlman) in their hotel room by singing "Hello, Little Girl" from Into the Woods. Luca (Simon Helberg) and Daniel (John Mulaney) have a running in-joke in which they repeatedly sing a few bars of "Old Friends" from Merrily We Roll Along, Jeffrey tells Luca that he has done a lot of community theater, including Sondheim's Assassins and "a production of Into the Woods that the Dutchess County Gazette called 'surprisingly good,'" to which Luca replies that "Assassins is criminally underrated," before he and Jeffrey break out into "Everybody's Got the Right" from that show. Daniel calls Sondheim "the best lyricist of the twentieth century." Several of the cast and crew of this episode have career connections to Sondheim: Richard Kind has been a cast member of a real Stephen Sondheim musical, the Goodman Theatre's 2003 production of the musical "Bounce" (also known as "Wise Guys" and "Road Show" in various incarnations during its development). John Mulaney cowrote and starred as the Sondheim figure in the Documentary Now episode "Original Cast Album: Co-Op," a close parody of the 1970 documentary Original Cast Album: Company (which chronicled the recording sessions for Sondheim's musical Company); Kind also starred in this episode. Poker Face showrunner Rian Johnson is such a big Sondheim fan that he not only often seeds his work with Sondheim references (for example, Benoit Blanc singing "Losing My Mind" from Follies in Knives Out), he also gave Sondheim one of his only onscreen acting roles: a cameo in Glass Onion in which he shared a (Zoom) screen with Poker Face star Natasha Lyonne.