"ESPer" aka "Jack of Eagles" by James Blish
This is a most peculiar book, written by the prolific James Blish in 1952, better known to most SciFi readers for the 'Cities in Flight' and 'After Such Knowledge' series as well as being the author of a run of twelve early Star Trek novels. It was his first full novel. Peculiar because it spends the first third or more as a standard pulp novel, even if it is above average in terms of its writing, about a G.I. Bill journalist who discovers his psy abilities. This gets him into a series of pickles that seem to culminate in a tale of gangsters and an FBI investigation. Then it suddenly switches tempo into something entirely different yet still coherently linked with the tale told before ... gritty newsroom realism morphs in stages into occult conspiracy and a cosmic fantasy that would do credit to Kuttner (to whom he dedicates the book) and Moore. What is remarkable though is that this is no cosmic space opera in the conventional sense. It is an attempt at hard science
