Chapter 40 starts off with Malory jumping around in a sort-of recap. First he reminds us of Sir Dinas, last seen at the end of the previous chapter! Sir Dinas has this little bit of backstory that Malory hasn’t bothered to mention up to this point, but which he feels he needs to bring to the fore (spoiler alert: it doesn’t matter). Once upon a time, says Malory, Sir Dinas had a special lady-friend, call her Monique, who had a second lover she preferred to Dinas, call him Lloyd. One day Dinas went out hunting, and Monique crept off to make time with Lloyd! She brought her two dogs with her. Apparently she had two dogs.
Dinas came home and saw that his lady-friend and his dogs had left.
“Oh no! Where are my dogs?” he cried. (Sir Dinas came home and missed his paramour and his brachets, then he was the more worther for his brachets than for the lady.) I guess Monique and Dinas owned the dogs in common.
Dinas had an idea where the dogs were, though: he headed over to Lloyd’s place and found them and Monique all romping with Lloyd. Dinas demanded Lloyd joust with him! Of course Dinas broke Lloyd’s arm and also his leg. Monique begged Dinas to spare Lloyd, promising to never cheat on him ever again.
“No way,” said Dinas. “You can’t trust a cheater.”
Then he took his dogs and left, and never saw Monique or Lloyd again. The end! Malory doesn’t seem to remember why he thought it was so important to tell us this story.
Instead he launches into a little reminder about how Launcelot, leader and founder of the Tristram Rescue Squad, continues to seek out Tristram. Launcelot can’t find him, though, on account of Tristram is locked up in Sir Darras’s castle with his fellow prisoners Sir Dinadan and Sir Palomides. Launcelot had been working with Dame Bragwaine, but she gives up and goes home to Cornwall. Launcelot ends up hitting Surluse, a country that comes up again a couple times later on (and which may or may not be in western Germany) with Kay and Gaheris.
So yeah, no rescue immediately forthcoming for Sir Tristram, last seen in a depressive episode (not his first) deep in Darras’s dungeons. Malory forgets he already explained the interpersonal dynamics among the prisoners back in Chapter 37, and goes through it again: Tristram despairs, Palomides berates Tristram, Dinadan defends Tristram, Palomides apologizes.
Tristram rouses himself to reiterate that Tristram doesn’t want to fight Palomides under these circumstances, that they’re stuck in prison, that Palomides is being a jerk, and that their real opposition is Sir Darras, who might have them all executed at any time.