Caine’s plan is devious, I’ll admit, but I’m not all that sure I’m ready to agree that it’s plausible. Having replaced the lug nuts and muffler and other parts of Buchan’s Lotus with painted gold, he arranges for Buchan to be recalled to England, where customs officers search the car. They’re not immediately ready to believe that he’s from MI-5 and they find the gold.
So what Caine wants to do, while actually moving the gold by boat, is convince Buchan that they’re scheming to smuggle it out £60,000 at a time on one hundred cars. I’m hopeful that Buchan won’t fall for this. Surely he’s going to realize that somebody tipped off customs, right? If they accidentally and randomly pulled him over, then it’s possible that they stumbled on the scheme, but the tip-off obviously means that Caine wants Buchan to think this is the real plan, meaning it’s a red herring. But will Buchan figure it out? The answers in the (hopefully) exciting conclusion, next time…
Fire Breathing Dimetrodon Time 
The most notable scene for me is right at the end where Mike & Sue climb the windmill. It appears that Adrian Wright and Wendy Padbury genuinely climbed the sails, it makes my palms sweat just watching it.