In 2008, while performing the Broadway play Equus, Daniel Radcliffe auditioned and got the part of Allen Ginsberg. Radcliffe went on to film the last two Harry Potter movies, Harry Potter and the Deathly Hallows: Part 1 (2010) and Harry Potter and the Deathly Hallows: Part 2 (2011), and with him unavailable for filming, Chris Evans, Jesse Eisenberg, and Ben Whishaw were cast without Radcliffe. Shortly after, financing for the film fell through. When director John Krokidas started again with the film, he offered the role of Allen Ginsberg back to Radcliffe.
In this film, David Cross plays Allen Ginsberg's father, Louis. In I'm Not There (2007), David Cross played Allen Ginsberg himself.
Filming on location was usually complicated by children passers-by freaking out at the sight of Harry Potter in the flesh.
Two years after their initial meeting, John Krokidas plucked up the courage to email Daniel Radcliffe once his project was back on track. Radcliffe replied almost immediately with "Abso-fucking-lutely."
Daniel Radcliffe and Dane DeHaan became very good friends while making the film, and were even roommates for a while.