During Will Ferrell and Harper Steele’s hilarious and heartwarming road trip, chronicled in director Josh Greenbaum’s film Will & Harper, the pair came up with many an ad-libbed diddy. “Will and Harper did a lot of singing, which, unfortunately for them, I cut out of most of the film,” laments Greenbaum (The Short Game). “But ultimately, they had this idea of: We need a theme song for our road trip.” 

So the pair, who’d met while working on Saturday Night Live in the 90s, called on another SNL alum to pen a song that would encompass the film’s messages of friendship and open dialogue. Will and Harper’s drive took them from New York to Los Angeles and allowed them time to connect about the changes in their lives — Harper had recently come out as transgender — and offered Will the opportunity to support his friend as she rediscovered her relationship with the dive bars and roadside stops she’d loved before transitioning, but where she now felt uncertain. 

After filming concluded, Greenbaum and songwriter and producer Sean Douglas got together with Kristen Wiig to work on “Harper and Will Go West.” “She had a lot written, and it was really wonderful,” says Greenbaum. “It’s a beautiful message: A friend is a friend until the end. I couldn’t have asked for a better gift to wrap up our film on.” 

Once they’d put the finishing touches on the song, Wiig and Greenbaum, who’d previously worked together on Barb and Star Go to Vista Del Mar, had the very serious task of filming Wiig performing her theme over the closing credits. “At some point, we’re like, we need a blow dryer blowing your hair in the wind as you play the sax,” Greenbaum says. “So, I was off camera blasting Kristen in the face with the leaf blower, just dying laughing. We had a lot of fun shooting that and editing it all together.”