This was the first Gold Dagger winner from anywhere but the UK, which struck me as so odd that I wrote to ask the CWA whether there was a nationality restriction prior to 1965. To my great delight, they actually wrote back. They said no.
A further oddity: I think this was the first winner to feature a well-established lead character (the previous winner introduced a character who went on to become established). The book is MacDonald's 12th of 18 featuring Lew Archer. I've read a couple of the others. In the early books, Archer is a fairly derivative Marlowe-style LA private eye in the Marlowe style. By this one, he has his own character and MacDonald his own style, out of Chandler's shadow.
Both character and style are, in a sense, minimal. Where Chandler's Marlowe is (for example) somewhat unsubtly erudite, Archer leaves the poetry stuff to other characters (mind you, MacDonald had a PhD in literature gained under the supervision of WH Auden, no less).. Where Chandler through Marlowe is given to some extravagant metaphorical flourishes, MacDonald through Archer employs only the most plain similes. There is a clear lineage, but also clear differentiation.
That said, this book offers a fairly Chandleresque proposition. A missing scion of a well-to-do family, a PI on the hunt, both scion and family gradually revealed to be harbouring secrets that can't go unrevealed if the case is to be solved. There is seedy LA underworld, there is a dame of sorts, there is a faint Hollywood connection—all the scenic elements you'd hope for.
The plot unravelled against that scenic backdrop is sufficiently gripping that you can overlook the fact that the middle third is essentially a sort of picaresque quest as Archer methodically follows lead A to find clue B from which to deduce fact C which provides lead D ... and so on. After all that, the parts are in place, and are gradually pulled together in a satisfyingly tight configuration, with just one piece held back to provide some last-page closure.
There is, arguably, more psychological depth and insight here than in Chandler; this is often said to be a way in which MacDonald managed to exceed as well as succeed his model. Mind, I do think that MacDonald's wife, Margaret Millar, is greater still at precisely showing human minds in all their particular peculiarities. MacDonald, incidentally, agreed that Millar was the better writer, and accordingly ceded to her the use of their real married name.
I am, frankly, a sucker for this kind of mid-century American detective fiction. It's not at all cosy—that's part of why I like it—but it feels somehow like sinking into something supremely comfortable, at least when it's done well. Perhaps it's partly the fact that, compared with the UK stuff I've read recently in this series, it's pleasingly, smoothly even in mood. There's none of the jarring shifts between whimsy and brutality you get in Keating, or Davidson, or the like. Humour is confined to occasional sardonic commentary, and otherwise you feel that Archer and his ilk will forever be cruising in unseasonal drizzle round the unglamorous fringes of glamourtown. I could happily drive around with them for eternity, too.