Summer Lightning is one of Wodehouse's Blandings Castle series, a series which is slowly replacing Jeeves & Wooster in my affections.
Most of the stories in the Blandings Castle series use the same plot devices: a broken engagement (or two), an imposter (or two), and the kidnapping of Lord Emsworth's pig, the Empress of Blandings. Summer Lightning is no different. Wodehouse gets a lot of mileage out of the old formula but it never fails.
Hugo Carmody and Ronnie Fish both end up on the outs with their ladies. Uncle Galahad is at Blandings writing his memoirs. Lady Constance wants the terribly efficient Baxter back as Emsworth's secretary. When the Empress turns up missing, Percy Pilbeam ends up on the case.
If you like Wodehouse, you'll love Summer Lightning. If you don't, get your act together. You probably spend most of your time beating up old women or something.