Proof, by Dick Francis
I have read all the Dick Francis novels -- he never delivers less than a good read. Proof is one of my favorites. It has an involving story, plenty of action, and a wounded hero who heals. Interesting details about the wine, liquor and catering business add to the usual horse racing milieu. The prose and structure here are among his most graceful, with parallel examples of the appearance and reality of courage. Proof makes great action story summer reading.
As a sidenote -- Dick Francis's strongest books came mostly in the eighties. Proof came out in 1985. I wonder if mysteries set around horse racing accorded better with that materialistic decade than with our own less certain time. My other favorites among his books include Straight, Hot Money, Break In, Come to Grief, Wild Horses and To the Hilt -- the last two are more contemplative and less active than the earlier books. His Odds Against and Whip Hand, I believe, were adapted as British miniseries.