Hetty is called on by a pair of worried parents whose deaf-mute son, Malcolm, has disappeared while out bird-watching on the day he was to meet his mail-order bride from Thailand. Malcolm is on the run because he has witnessed the strangulation of a beautiful model-turned-journalist by her lover, Sergeant Steve Lennox, a rogue policeman. After doing the deed, Lennox sends the woman's body over a cliff in a car - and takes off after Malcolm. Hetty and Geoff's search for Malcolm proves more difficult than expected - especially after Sergeant Lennox is assigned to work with Hetty on the case!
