H. L. Lawrence wrote only two books. The other one, called both The Children of Light (1960), is the better-known of the two, since Joseph Losey based his Hammer-thriller The Damned on it - and it's a pretty good film, too, almost completely without the usual clumsiness of many Hammer thrillers. Lawrence's other book is called The Sparta Medallion and it was published one year after The Children of Light.
It's a pretty solid thriller, with a decidedly British bent on it. It stars a British geologist on his way to South America. He meets a strange German in the plane. The plane crashes however and only three people are left to survive: the geologist, the German and an air hostess. The German is killed in the jungle in mysterious circumstances, the air hostess is captured by the Indians and the geologist is left to survive in the jungle with the German's stuff, so when he's found he's thought to be the German. The man finds out soon there was something mysterious about the German and his belongings, and as he reaches Lima, several people are trying to kill him and take the suitcase that belonged to the German. The geologist however makes nothing out of the stuff therein.
It all comes down to a large, world-wide conspiracy that harks back to the Nazis, but Lawrence deals with it nicely in just 160 pages (I checked: the British first hardcover edition has 160 pages, the Finnish paperback has 139 pages). Nothing larger than life, just a nice solid thriller. It's a wonder Lawrence wrote nothing more. If someone has an explanation, I'd like to hear. Seems like he worked in advertising, maybe he ran out of time to do extra work.
More Forgotten Books here.