The Heliades are Greek Nymphs, the seven daughters of Helios, God of the sun, and the Okeanid (Nymphs who presided over the natural water sources of the Earth) Klymene. They also had a son, Phaethon, who pleaded with his father to let him drive his chariot across the sky. Helios reluctantly agreed and Phaethon lost control of the horses and drove too close to the earth, scorching it. Zeus struck him down with a thunderbolt to stop the destruction, and Phaethon fell to his death in the River Eridanos. His sisters, the Heliades, gathered there to mourn him, and when they cried, Zeus turned them into trees. The trees cry still, shedding golden drops of sap that turn to amber when they fall.
The year is 1980, and Harry Thursday is about to be drawn into another thrilling adventure. He has come out of retirement, and has been working on a tiny Greek island resurrecting the decrepit Temple of Zeus there.
Meanwhile, back in Pennsylvania, his uncle falls to his death at the Harrisburg train station, an accident they call it, and Harry is called back to the states by the uncle's attorney, a sexy intelligent lawyer with a few secrets of her own, who is counsel to some very wealthy clientele.
When the police mention to Harry that a small piece of amber was found lodged in the dead man's throat, Harry suspects foul play. Soon, Harry's time on Earth is becoming tenuous.
This is the subject of the 3rd Harry Thursday novel, which if I can stop delaying, will be finished before the end of the year.