Malachi Martin (July 23, 1921 – July 27, 1999) was an Irish-American writer, former Jesuit priest, and theologian. He served in high-ranking Vatican positions before leaving the priesthood due to his criticism of church reforms. Martin is best known for his books on secrets and conspiracies within the Catholic Church, such as 'The Keys of This Blood' and 'The Jesuits.' His works often explore power struggles, mysticism, and eschatology, sparking widespread controversy. A polyglot, he mastered several ancient and modern languages. His life was marked by transformation from theologian to author, always focusing on deep religious and societal issues.