Mark Twain got his idea for Hank Martin to use the eclipse for his benefit from Christopher Columbus who used an eclipse knowingly to perhaps alter history. Stranded in Jamaica in 1503, on his fourth voyage, Columbus and his crew were wearing out their welcome with the natives who were feeding them. Columbus knew a lunar eclipse was coming, so he "predicted" the moon's disappearance. The natives begged him to bring it back and, of course, he did in due time.
The filmmakers couldn't use the musical's original score because it had already been purchased for use in Words and Music (1948), a Richard Rodgers tribute.
Bing Crosby insisted that first-time Paramount contractee Rhonda Fleming share star billing with him because he was worried about carrying the sole weight for the film's success or failure. Ultimately, they both were billed below the title in the opening credits, sharing a card with William Bendix and Cedric Hardwicke.
It was hoped that the song "If You Stub Your Toe On The Moon" would be as big a hit as Bing Crosby's previous hit "Swingin' On A Star", but it never caught on and was never put out on records.
Deanna Durbin, on the verge of retiring from the screen, turned down opportunities to co-star with Bing Crosby in this film and his previous vehicle that year, Top o' the Morning (1949).