Polly was never given a last name in the series. According to production notes, she was meant to be Polly Wright, but this was not used in case it would be confused with earlier companion Barbara Wright. In "The Faceless Ones", a double of Polly is named Michelle Leuppi; an apparent mishearing of this and misinterpretation of the context led to some reference works giving Polly the last name of "Lopez". Anneke Wills suggested the name "Bettingham-Smith", after one of her friends. In the Virgin Missing Adventures novel "Invasion of the Cat-People" by Gary Russell, Wright is expressly given as Polly's last name, as it was supposedly given in Gerry Davis's character breakdown and audition script sample when, as story editor, he and producer Innes Lloyd created Ben and Polly in 1966.