Gil Kane is joined by John Celardo for The Hawk and the Dove 6 (June/July 1969), the final issue of the series.
At the top of the story, Hank and Don Hall interrupt an attempt to kidnap their father. Hank changes to Hawk and tries to catch the man behind it, while Don stays behind to look after his dad. The difference between the two is neatly and effectively played out in this scene. Neither thinks the other chose the right course of action.
The following day, coming home from school, the boys find their mother beaten, and their father taken. Once again Don stays to tend the parent, and Hawk takes off. He is furious, and determined to hunt down the man who took his dad.
Once again, Dove is shown to be the thinker. He does some research, and discovers that their gardener is the son of a man his father had sent to jail. This seems a likely case of motive and opportunity.
And Dove is right. The gardener is the kidnapper. He is determined to seek vengeance after his father died in prison. Judge Hall does not regret his actions, but does show sympathy towards the man, understanding his anger. Dove reaches his father first, but takes time to come up with a safe way to rescue him. Hawk gets there, and just barges in. Although he does save his dad, the father almost gets shot in the process.
As the series concludes, Judge Hall has little good to say about Hawk and Dove, despite the rescue, feeling that they are not able to use their abilities wisely. This really cuts the brothers, who debate whether they ought to give up being superheroes. The end makes it clear that, unlike the last few books, the writer knew this would be the final issue.
But Hawk and Dove did not give up their crime fighting lives, and would return a couple of months down the road, joining the Teen Titans.