Murderer's Fen by Andrew Garve
Alan Hunt is ambitious and unpleasant - a caravan salesman with good looks, youth and charm. He is engaged to be married to Susan, a plain girl with a beautiful fortune.
Just two weeks before the wedding, Gwenda Nicholls turns up, a pretty redhead he seduced on holiday in Norway: lovely, trusting - and pregnant. She threatens Hunt's new way of life, insisting on marriage, so he forms a plan to get rid of her - permanently - and knows the perfect site to hide the body.
A master of suspense at the top of his form. Evening News
Guaranteed to bring gasps at his ingenuity. Sun
Distinctly gripping study of a coldly narcissistic salesman-seducer . . . Observer