“Sunday Girl” is a song recorded by the American new wave band Blondie, from the band’s 1978 album Parallel Lines. Written by guitarist Chris Stein, the song was inspired by Debbie Harry’s cat, who was named Sunday Man—the cat had recently run away, inspiring the song’s “plaintive” nature. “Sunday Girl” was released as the follow-up single to the band’s number one hit single, “Heart of Glass,” in the UK and Europe (though not in the US). The single was a number 1 hit in the UK and Ireland and reached the top ten in several European countries. It has since seen critical acclaim and has been included on several compilation albums.