"The Mixed Men" by A. E. van Vogt is a novel created from three previously released works as well as a new section linking them together. It was first published in 1952. As one would expect with shorter works of fiction, there is not a great deal of time spent in character development, and this problem was not corrected in the creation of the novel. The result is a decent, but far from great work of fiction. These stories are collectively known as the Dellian Robot series, and all the stories from this series are included. The novel was also published under the title "Mission to the Stars".
The novel takes place in the far future, as an Earth ship discovers a human far from where any should be. They quickly learn that he is a Dellian. Dellian Robots are not actually robots, but instead are a group of humans which were altered by the use of a matter transmitter. It made them less creative, but much stronger than normal humans and less subject to nervous strain. After hatred and bigotry forced them to flee, along with some non-Dellian humans and they had remained hidden for fifteen thousand years. During that period, Dellians and non-Dellians had found a way to breed, the offspring being known as Mixed Men. The novel falls easily into the four sections from which it was created.
Preface: This was first published as the short story "Concealment" which was originally published in "Astounding Science Fiction" in September of 1943. In this story, the Earth ship, Star Cluster, discovers Gisser Watcher, a Dellian on a meteorite weather station. He realizes the ship's origin and tries to destroy himself, but the Earth ship contains technology far beyond what he anticipates. This story introduces the Lady Gloria Laurr, the Grand Captain of the Star Cluster. It also introduces Lieutenant Neslor the psychologist who examines and questions Gisser Watcher and ultimately realizes what he is.
Chapters 1 - 7: This is the linking material written specifically for the novel. It was also published as a novella under the title "Lost: Fifty Suns" in a book of short fiction under the same title in 1972. In this story, the Star Cluster searches for the 50 Suns of the Dellians. Lady Laurr broadcasts messages to the citizens of the 50 Suns (located in the Greater Magellanic Cloud) announcing that Earth knows they are there. She promises benefits for the first to come forward in an attempt to get one group of Dellians to betray the location of all. This story introduces the Mixed Men, and their hereditary leader, Maltby. In this story we learn just how much more powerful the single Earth ship is than the entire 50 Suns, however, the abilities of the Mixed Men are also learned and provide a significant advantage to Maltby.
Chapters 8 - 15: This was first published as the novelette "The Storm" in "Astounding Science Fiction" in October of 1943. This story includes the attempt to trick the Star Cluster into destroying itself, and more on the incredible technology of Earth as they thwart the efforts of Maltby and the Dellians. This also includes the greatest amount of character development in the novel, as Maltby is forced to fall in love with the Lady Laurr, and an accident resulting in their being stranded on a planet together results in her falling in love with him the natural way. In the end they are rescued, and a marriage is implied.
Chapters 16 - 23: This was first published as the novelette "The Mixed Men" in "Astounding Science Fiction" in 1945. It was also nominated for a retro Hugo in 1996 for novelettes written in 1945. This is easily the best part of the book. The story covers Hunston taking control of the Mixed Men and leading a revolt against the Dellians in an attempt to take control and defeat the Star Cluster. Maltby is not trusted by the Mixed Men, and is left behind by the Star Cluster. He is forced to find his own way back to his wife, learning that he has gained some support among the Dellians.
All in all, these are a decent set of stories, but they really work much better when taken as short fiction rather than as a novel. None of these stories are particularly easy to find, and this is especially true of the last one. If you enjoy early science fiction, then this is a good book to pick up if you can find it.