A mythological novel by Mary Renault published in 1958, telling the story of Theseus from Theseus' own point of view. She instills new life into the myth with entertaining dialogue and narrative. A memorable line occurs when Theseus is asking his mother who his father really is, Aegeus (her husband) or Poseidon (the god of the sea, noted for his lust). To avoid offending her by implying she committed adultery with Poseidon, he tells his mother, "Don't be embarassed that you got a child from it. It happens to girls I sleep with, and I don't think any less of them" (or something to that effect - it's been a while since I read it). Theseus is gallant and upstanding, but apparently he is no angel!
Whereas the myth tells us cryptically little about the relationship between Theseus and Ariadne, Renault portrays the two in great detail, making the reader sympathetic to them. When Theseus abandons Ariadne on the island of Naxos, Renault gives us a reason why; I have never seen this explained in the myth. I found it to be the most poignant part of the book, so I do not want to ruin the surprise - but for the insatiably curious, I will describe it below in ROT13. You can decode it by pasting the text into the E2 Rot13 Encoder.
<ROT13>
Gurfrhf qrpvqrf gb yrnir Nevnqar ba Ankbf nf fur frrf ure pryroengvat jvgu gur erfvqragf bs gur vfynaq. Gurl trg qehax naq sebyvp nyzbfg gb gur cbvag bs betl, naq Gurfrhf gryyf uvzfrys gung Nevnqar, nf tbbq n ybir nf fur vf, jbhyq ungr gb yvir ba gur znvaynaq bs Terrpr, jurer yvsr vf zber fgnvq. (Gung vf engure avpre guna uvz "nonaqbavat" ure, ab?)
</ROT13>
I read The King Must Die many years ago, and found it deep and exciting at the same time. I recommend it highly.
Wikipedia informs me that there was a sequel to the book, entitled The Bull from the Sea, published in 1962.
A nodeshell rescue.