From USA:

Make art history palatable and exciting for a large audience.
Los Angeles Times

For fans of religious conspiracy and reinterpretations of religious history.
The Washington Post

''The Secret Supper'' is a fascinating yarn and very well told.
San Francisco Chronicle

Sierra emerges as a strong contender in historical fiction with his mostly well-crafted book.
Rocky Mountain News

Javier Sierra's take on Da Vinci is much sharper, more focused and more rewarding.
New York Daily News

No mere "Da Vinci Code" redux, this Spanish bestseller fuses an ecclesiastical whodunit with an A-Z guide to Neoplatonist philosophy and Renaissance symbology. Sierra is a more sophisticated writer than Dan Brown, and he offers fresh perspective on the Renaissance mind.
Kirkus Review

Offers a new way of interpreting The Last Supper. Sierra’s book, already a bestseller in Europe, is a fresh contribution to the Da Vinci industry.
Publishers Weekly

From United Kingdom:

Sierra's scholarly approach has produced an intriguing literary thriller.
Susanna Yager. Sunday Telegraph

Here, at least, is an author who knows how to put the doxy into heterodoxy.
Boyd Tonkin. The Independent

Leonardo da Vinci painted his own face into The Last Supper, reports the Sunday Telegraph. Spanish novelist Javier Sierra used police recognition software to match disciple Judas Thaddeus with a Da Vinci self-portrait. His subsequent thriller has sold 500,000 copies and is being fought over by studios eager to emulate The Da Vinci Code phenomenon.
Independent on Sunday

Sophisticated, memorable and much more than an ordinary detective story.
Books Quarterly

Another religious conspiracy thriller - Javier Sierra's The Secret Supper - looks set to sweep the world.

A new novel, based "90 per cent on historical facts", depicts Leonardo Da Vinci as a heretic who painted his own face into The Last Supper, and claims that the painting portrays Saint Peter as a traitor and carries a blasphemous message. The Secret Supper, which has sold more than 500,000 copies in Europe, is set to rival The Da Vinci Code for conspiracy theories about one of the most famous figures in art history.
Sunday Telegraph

From Australia:

Highly recommended.
Canberra Times

The novel contains many of the period's scurrilous anecdotes...and evokes the debauchery and intrigue of the time with great elan.
Melbourne's The Age

Any comparison between Sierra and Brown is similar to pitting a Renaissance painter against a graffiti artist.
Alan Gold. The Weekend Australian

This is medieval mystery with literary elegance.
The Weekend Australian

From Canada:

Even if you hated "The Da Vinci Code", you'll love this one.
The Globe and Mail

This is a great, fat wallow of a book, fun to read, full of strange lore and tidbits.
The Globe and Mail

Javier Sierra has written a scintillating murder mystery.
Toronto Star

Javier Sierra is undoubtedly the first real challenger Dan Brown has faced since he hijacked the bestseller's lists three years ago with his interpretation of Da Vinci's work.
The Ottawa Citizen

From Spain:

All those who where fascinated by "The Da Vinci Code" will be swept away by this surprising novel, which in no sense resembles Dan Brown’s but rather is based upon absolutely original discoveries. Those who were dissapointed by the ending of "The Da Vinci Code" will be moved by this (The Secret Supper’s) ending, with it’s truly authentic revelation.
Año Cero

In a time when the greater part of Modernism has spent the last half century glorifying banalities, stories like this one restore our faith in the purpose and power of artistic expression. We have here a great book, the best in our judgment that this author has written to date.
Más Allá de la Ciencia

An entertaining, ingenious, fluidy written tale, with a simple style that permits the reader at the same time to appreciate the enormous array of facts underpinning the novel’s theoretical premise.
El Periódico de Aragón

From Italy:

Javier Sierra has a particular talent for mixing science and occultism, theological enigmas and mundane plots, to solve ancient mysteries and to understand artworks.
Il Messagero