Gone Wild is a disappointment.

It starts badly, lost in the lush, swampy Borneo jungle. Allison Fairleigh has taken her two grown-up daughters -- the disturbing appointed Winslow and Sean -- on the annual orang-utan census, surveying the movement of the great apes man threatens with extinction. It's extinction though that threatens the Fairleigh family when they cross animal smugglers and Winslow is murdered.

Cut now to Florida. Allison is gripped with a crisis of faith. Her one-woman crusade against the illegal animal trade has cost her a daughter, her marriage to politically powerful Harry is fragmenting, and Sean seems to be falling for the unctuous, connected, filthy-rich Patrick. But even as Allison wants to leave her old life behind she finds herself sucked right back in and calls for help from old friend (and Hall regular) Thorn.

James Hall's sixth novel, like the first three, is heavily aware of its environment. Detrimentally so. Books like Under Cover of Daylight and Bones of Coral proved him capable of carrying a tale, but were sufficiently weighed down by enough eco-warrior mannerisms to nudge the switch over towards worthy but dull. Only the more recent Hard Aground and Mean High Tide, with their wayward plotting and vicious black humour, really came good. Gone Wild reads like the unholy alliance of both Halls, although that said, when it's good it's very good indeed.

Step up the demonic twins Orlon and Ray, Florida animal smugglers and as charming a double-act as Hall has yet served. Ray is the tall, blow-waved Beach Boy -- brains of the operation. Orlon, the antithesis of his brother -- is short, a movie geek taken to a daily ritual of plucking and shaving every hair from his corpulent body. Both favour firearm diplomacy to smooth over little local difficulties, but the thin line between amoral and sociopathic is one that Orlon increasing misreads. Corpses start to pile up, Ray's relationship with his psychiatrist begins to contravene her code of ethics, and as readers we bemoan their absences from the book.

Hall has a way with a bad guy that can't translate the other way: Allison, Thorn, Sean -- it's hard to care. But that's as nothing to the scattergun plotting. When the twins are before the camera things move like lightning, and the Allison episodes in Florida at least keep things moving, but the continuing adventures of a captured orang-utan and, in particular, Sean's romantic interludes become increasingly tiresome. Too much of this is going to serve a grand conspiracy that is just plain batty. The pat resolution is both stodgy and unnecessary.

This is a crisis book for Hall (who seems to acquired a 'W' from somewhere, all of a sudden). It wants to be Gorillas in the Mist via Elmore Leonard, but ends up as James Bond schtick by way of Greenpeace. When he sat down to write, Hall had a little too much agenda in mind. His cast too easily wear white and black hats, and it's a truism that the most interesting guys always wear the latter. Unfortunately for us, Hall spends too long with the rest.