Susan Martin (Jane Powell) is the decoy duck. White travelling in South Africa she purchased some diamonds from a man called Bert Landon.
Now she has been arrested by cop, Reginald Kettering. He gives her a way out but only after she signs a confession.
To help arrest rogue diamond dealer Jim McCandless (David Janssen.) Kettering has been after him for a while.
Susan agrees but finds McCandless to be ever so charming.
To be sure to everyone that Kettering is a rogue cop in league with Bert Landon.
They set up Susan and then use her to swindle McCandless.
I guess this is a story where Susan could not run to the cops. Maybe she should had headed to the US Embassy.