One of the most memorable of the theme songs, though musically not up to the quality of some such as "Maverick". The ads were a bit silly: "Beneath this salesman exterior..." caused my waggish brother to quip "beats a heart of gold". But though relatively short-lived and suffering from Warner's rehashed scripts, Preston was suitably solid and stolid; and yet, perhaps because of the tie in to the Colt revolver, and the undercover agent aspect, it was great fun!