Set five years after the events of Montmorency, Eleanor Updale's sequel to her loveable anti-hero has him basking in the wealth and glory that comes with being a patriot and spy for his country. That is, he would be if it weren't for the opium addiction he picked up whilst traveling undercover in the East. His friend George Fox-Selwyn is desperate to wean him off it, and so destroys his stash and spirits him away from London society to his brother's house in Scotland. From there, the two men end up on a remote island off the coast where the inhabitants are suffering a under a strangely high infant mortality rate. Joined by their friend Doctor Farcett (who is himself suffering from a crisis of faith after he accidentally kills a man on the operating table) they begin their investigation.
The doctor's presence is welcome to the people of Tarimond Island, but Montermerency lives in fear of the good doctor - for he is the only man who could identity Montmerency as prisoner number 493, being the doctor who treated Montmerency after a devastated fall that left numerous scars across his body. After leaving prison Montmerency made his current fortune by using the underground sewer system to steal from the wealthy; and it's a secret that he still conceals from his friends to this day.
But meanwhile, a bomb has gone off at a London train-station, and though the authorities manage to blame it on a gas leak, it's suspected that insurgents seeking to undermine the government are responsible. Once again Montmerency must call upon his disreputable alter-ego Scarper to find the culprit and bring him to justice, the clues leading him to the proprietress of a boarding house that - like him - has to make the transition from poor to rich in order to disguise her true identity. But Montmerency's opium addiction means that he's constantly in danger of loosing his inhibitions and exposing his true identity. Thus the title of the book not only refers to the rocky island off the coast of Scotland, but the fact that Montmerency is figuratively "on the rocks" when it comes to his personal wellbeing.
"Montmerency on the Rocks" is, like its predecessor, an enjoyable but unique story, largely thanks to its unexpected plot. That is, they're unexpected because they're so straightforward. At the risk of making the book sound dull (which it certainly is not), there is no melodramatic flair or dramatic plot twists here. Everything unfolds at a steady pace. The character's plans are achieved with no major setbacks. Temptation is not succumbed to. Angry mobs are reasoned with. All of it is told in lovely clear prose, but some readers might be surprised by how "easily" Updale lets her characters overcome their challenges; it's not that intelligence and hard-work isn't involved, but that there are no convoluted attempts to make difficult situations *more* difficult.
It's oddly refreshing and it lends a sense of realism to the proceedings that is often lost in many "cloak-and-dagger" novels, and yet Updale still manages to infuse the book with several moments of insight and moral complexity - the man who is blamed for the "gas-leak" eventually commits suicide, but only the reader is privy to this information as the protagonists obliviously congratulate themselves on the cover-up.
Another unusual feature is the dual plots. The bomb and the sickness are completely unrelated, are solved in different ways, and never intersect with one another (though they are thematically related). Likewise, Montmerency's drug addiction is dealt with early and has little bearing on the rest of the story, making the book a three-pronged tale that has pacing which would be downright bizarre if it weren't for the obvious talent inherent in Updale's writing style. She's wonderfully descriptive, from the busy streets of London to the bleak landscape of Tarimond Island, and it's impossible not to feel immersed in the vivid setting that she's created for her flawed but honorable three-dimensional characters. Throughout this series, even the so-called "villains" are worthy of sympathy and understanding.
Unusually for a children's or young adult's book, most of these characters are adult males, but there's no reason at all why the target audience shouldn't thoroughly enjoy what the "Montmerency" books have to offer.