In the sequel, Chesney faces new problems. Specifically, the Reverend Billy Hardacre is attempting to become a cowriter on the new edition of the world - it's a very literary theology - and unfortunately, that involves casting Chesney in the role of prophet. Chesney's new girlfriend, Melda, also wants in on the action: she's thinking more along the lines of corporate sponsorship. And rumours abound of a new draft of the book; the police are investigating Chesney's crime fighting persona; and many things are fairly stuffed (to summarise).
Unfortunately, with these additions, Costume Not Included neglects one of the key aspects of the original title. Damned Busters was a flawed but enjoyable deconstruction with a quirky literary view of theology. Its sequel neglects that first part - the 'enjoyable'. Subplots, such as the struggle against the city's corruption, are left dangling as the focus turns solely to the 'new draft'. Which, as it turns out, really isn't sufficiently interesting to sustain a novel - particularly with the likeable Chesney's role slightly peripheral. Costume Not Included tries for a complex plot: subversions, schemes, and nested betrayals. It's only unfortunate that to the reader, it looks like a mess.
Long-time SF readers are likely wary of time travel: as a plot device, it's known for introducing plot holes as well if not treated carefully. Costume Not Included introduces this once more - and in my opinion, it doesn't work. Chesney's arrangement with Xaphan was previously powerful, but limited: he had the powers he asked for, but it was entirely possible to beat him for lack of those he didn't. (The pepper spray being a particularly amusing instance of this). But if your protagonist has the (apparently unlimited) ability to time travel as well? That was the sound of tension draining away.
This isn't to say Costume Not Included is all bad: far from it. Hughes writes as engagingly as ever; Chesney is a likeable if flawed protagonist, and the core concept did have potential - it's a quirkily interesting worldview, if nothing else. But the series suffers from the derailment of its key premise in this particular sequel; and the lack of a truly characterised female (Chesney's mother is severely flawed; and Melda's enthusiasm for sponsorship of crime fighting really says it all) lets the novel down. Original and concise, but this sequel wasn't for me.