What is the climax in the novel, We Begin at the End?

The novel has multiple climaxes, the first coming when Star is murdered. There is more exposition when Duchess and Robin move in with Hal and begin to settle into a life with him. Whitaker builds to a climax with Duchess’s warnings to Hal that Darke is coming for her. The climax comes when Duchess returns home to find Hal has been fatally shot by Darke.