The fourth book in the Jake and Jouma series sees our two protaganists separated and that, I'm afraid, is where the rot starts to sink in. Jake and Jouma are two very different personalities and they rub off well against each other. By separating them, Nick Brownlee was running two parallel stories,neither of which had the potency and buzz of the earlier books in the series. Jake's shipmate Harry features quite heavily in the story but is like a loose cog without Jake to keep him in check.
The plot is quite hard boiled and the action is often brutal. You could argue that this is no surprise being that the action takes place in a largely lawless country, but it doesn't jibe with the earlier books and, to my mind, is a step backwards for the author.
Next time round, I hope Mr Brownlee keeps his two protagonists without spitting distance of each other. They are shadows of their former selves when separated.