A taut little IRA thriller--with a busy, if foolish, plot that leads up to a St. Patrick's Day assassination on the steps of N.Y.C.'s St. P.'s Cathedral. (An inescapable echo here of Nelson DeMille's Cathedral.) Martin King, an English soldier in civilian clothing, spying in IRA-infested Crossmaglen, is assassinated one night by J. S. O'Hara--a Manhattan narcotics cop and IRA hit-man who's flown in especially for the job. And when Martin's brother Peter, an alcoholic N.Y. reporter, flies over for the funeral, he finds that his brother's death is being thoroughly hushed up. So, while killer O'Hara is going somewhat bonkers back in N.Y. (wife/mistress trouble), Peter sleuths around Ireland and England, evading bombs and closing in on the killer's identity. And the trail leads Peter back to America--where O'Hara has decided to assassinate a senator and a cardinal (both of whom he thinks of as turncoats on Irish patriotism.) Complete with the inevitable countdown/showdown to assassination: a predictable recycling of a highly familiar scenario--but Burton (The Coventry Option) keeps it moving fast enough, with nicely rough-hewn characters and sturdy IRA details, to maintain steady interest for assassination-thriller aficionados.