Car Ride

Saw this film at the Cinema when I was but a child (Clifton Cinema - Tower Hill Birmingham - no longer there sadly)and watch it at least once a year .(Along with Evil under the Sun.)
Both very entertaining, but one thing has bugged me for years
Jackie and Simon obviously had a plot to marry and kill Linnet from the get-go so why, when they were driving to Linnet's were they talking like they were being bugged. Jackie saying things like - "We'll honeymoon in Egypt".

I know it would spoil the film early on but I feel they would have been much more nervous and would be talking things through about the "Grand Plan".

They were talking like Jackie was about to introduce Simon to her friend Linnet and Jackie and Simon had plans beyond the meeting of Simon and Linnet when the plan all along was for Simon to seduce Linnet and leave Jackie.

UNLESS I missed something and that was not the plan at that point, then, Boy, would I feel sheepish. 40 years of misunderstanding a major plot point.

'tler