There's a famine. Divinely commanded of course. David asks god what's up, and he says it's punishment for the time Saul killed all those Gibeonites. Except... Saul didn't kill any Gibeonites. Remember? They tricked Joshua into signing a treaty all those books ago. According to Jerry, Saul violated that treaty, which isn't a very satisfying answer. And of course he doesn't bother to address why, exactly, god is turning against his chosen people for another people for a crime committed by someone who is already dead.
In the very next verse, we find out that Saul only sought to slay the Gibeonites, not that he succeeded. David goes to their king and asks how he can atone for Saul's crimes. The king asks for seven of Saul's descendants, and David chooses two of his remaining sons and five of his grandsons, including five of his ex-wife Michal's sons. Way to stick it to your ex, David! You're a model for psychotic ex-husbands everywhere!
The seven men are hung on a hillside in Gibeon. Rizpah, one of Saul's daughters, sits under the trees and chases off the carrion birds.
David hears what Rizpah's doing and he gathers Saul's and Jonathan's bones, then the bones of the seven hanged men and buries them on consecrated ground.
This book is very bad about transitions. In verse 14, David's praying to god for forgiveness for Saul's crimes. In verse 15, the Philistines invade again. Wouldn't that be better as the first verse in a new chapter? But I digress. The Philistines have giants again. First Abashai kills Ishbibenob, the first giant. Then there are several more, including Goliath's brother. Finally, one comes along with extra fingers and toes and is killed by David's nephew. That's the end of the giants for now.