Brown's "Angels and Demons," a thriller that includes purported details on the conclave — the secret gathering of cardinals that picks the next pope — has seen a "significant" increase in sales, according to publisher Simon & Schuster. CBSNews.com and Simon & Schuster are both part of Viacom, Inc.
The conclave to choose Pope John Paul II's successor is scheduled to begin April 18.
"We attribute the increased sales to interest in the cardinals' conclave," Simon & Schuster spokesman Adam Rothberg said Monday.
Published in 2000 and featuring "Da Vinci Code" protagonist Robert Langdon, "Angels and Demons" already has more than 8 million copies in print. Much of that is thanks to "The Da Vinci Code," which came out three years later and has 25 million copies in print.
Cardinal Tarcisio Bertone, a former Vatican official considered by some as a possible candidate for pope, has said that "The Da Vinci Code" espouses heresy. Allegations in the novel that Jesus Christ married Mary Magdalene and has descendants have outraged many Christians and have been dismissed by historians and theologians.
The church has not criticized "Angels and Demons," although some details of its depiction of the conclave have been questioned in "Secrets of Angels & Demons," a collection of commentaries co-edited by Dan Burstein and Arne de Keijzer.
"Everyone should understand that it is fiction," Burstein said. "As it happens, a great deal of the information he presents about the history of the papacy ... is actually quite close to being accurate."