We have seen Jon become more obsessed about helping children through the series, and we have learned the story of his past (Children No More). We get a little more about his early life after leaving his home planet, but it is just the set-up to his meeting with a woman he ran away from more than a century earlier. That incident simply reinforced his well-founded feeling that anyone learning too much about him would want to put him back in a lab.
In this book, Lobo (through the plot device of messages for Jon in case of Lobo's demise) lets us know that he has figured out Jon's secrets. Well, given his speed and the amount of time and information Lobo has had, he should have. And we learn another of Lobo's secrets, which I expect will be more utilized in the future. It's a big secret, and something that could be exploited by our heroes in the future.
The book begins with a hastily planned rescue of kidnapped children, who are to be auctioned off to very rich pedophiles. Van Name introduces some irony by having the host note that 25% of the prices will be donated to children's charities. Feel good while doing bad... Jon & Lobo pull it off, but a very powerful man sees Jon's face and promises revenge. Jon should have just killed the slimeball, but then he would not have been Jon. Lobo worries about Jon's increasingly reckless behavior and is planning to sacrifice himself if need be to save Jon.
Next Jon gets a message that his first lover is dying and wants to see him. This provides a nice little bit about the perks of buying stuff when money is not an object, as Jon prepares to meet the woman while disguising his age and protecting himself against treachery, which he and Lobo must anticipate. But he also learns that he has not been quite careful enough about concealing his past.
But Jon also learns that there is someone out there who has not only stopped aging, but even been restored to youth. One possible scenario he imagines involves the work of his sister, lost for nearly 140 years. So he does need to investigate. This leads to an infiltration plan which embeds him in the traveling group supporting a star singer. We get another taste of how Jon & Lobo can plan an execute an operation.
There is a built-up tension as Jon is increasingly moving into confrontations with powerful people who want to either destroy him or use him. But he cannot run away and Lobo anticipates the worst.
There is the usual grousing from Lobo about being treated as a menial machine. We get the "I live to be your ..." a couple of times. At least Lobo is not depressed, like Marvin from "The Hitchhiker's Guide to the Galaxy."
About the ending, I will only say that there is hope.