The Saint Bids Diamonds by Leslie Charteris
The Saint's holiday in Tenerife comes to a dramatic end when he rescues an elderly Dutch diamond cutter and his daughter from a vicious attack. It seems the old man is a reluctant member of a jewel-smuggling gang, and naturally Simon offers to help him out for just a small share of the boodle. But things get complicated when the Saint learns the old man had a lottery ticket worth $2 million - which has now gone missing. As the plot gets more complex, Simon struggles to play a winning hand.