The story tells of a young priest sent by the authorities in Rome to fully implement Church reforms in an Irish monastery that still celebrates the Catholic liturgy according to older rites.

In this novel, there is lacking that positive sense of the individual bearing witness to his faith... which emerges so strongly from Cold Heaven, from Black Robe and from The Colour of Blood".

[1] Moore also wrote the screenplay for the 1973 television film version, which stars Trevor Howard, Martin Sheen, and Cyril Cusack.

Falls directed[3] a cast that included David Frederick White (as "Tomas O'Mallery"), Tony Amendola (as "Brother Kevin"), and John Aylward (as "Father Walter").

In addition to this, several phrases within the book (and the later film) have been claimed to be comparable to rhetoric typical of a Sedevecantist sect, that is in schism with the Catholic Church.