Another Da Vinci code is emerging from Leonardo’s masterpieces, according to a forthcoming book by group of Da Vinci theorists who believe that biblical images are hidden within the master’s artworks.

Worthy of a Dan Brown novel, the claim identifies Leonardo’s mirror writing as the key to unlocking the code.

The Renaissance genius, who lived between 1452 and 1519, filled thousands of manuscript pages with a unique handwriting that flowed from right to left and reversed all the letters.

Scholars have believed that the artist developed this impossible writing simply because a left-handed Leonardo would have evolved a style of handwriting efficient for him.

But, according to Hugo Conti, a self-taught Argentinian historian who leads a mysterious group called “The Mirror of The Sacred Scriptures and Paintings,” the writings conceal much more — a key to secret images.

“It is easy to find invisible images in Leonardo’s paintings. Many of his characters seem to be staring into space. In reality, they are indicating where one must place the mirror to visualize the images,” Conti told Discovery News.

When applied to Da Vinci’s painting “Saint Anne, the Virgin and Child,” on display at London’s National Gallery, a mirror reveals a figure which some cynical observers say looks like the Star Wars character Darth Vader.

According to Conti, the image resembles the ancient Old Testament god Jahveh, who represents the human mind’s struggles against the vices of the body.

A similar face appears on Mona Lisa’s right shoulder, as a mirror is placed right on a spot pointed at by her finger.

“The Last Supper,” in which other probes have so far revealed a hidden Mary Magdalene, a woman holding a child, and a musical script, reveals a key image when a mirror is applied. According to Conti, one can see the Holy Grail itself overturned on the table when viewed with a mirror.

“The glance of the apostle James is not directed to Judas, but to where the Holy Grail, only viewable through a mirror, is overturned on the table, just between Jesus’ hands,” Conti said.

Conti says another biblical image is hidden in Leonardo’s painting of John the Baptist, on display at the Louvre Museum.

Again, John the Baptist’s finger points to where one must place the mirror.

The result, at first glance, is a woman being bonked by a tree. Conti believes it represents the Tree of Life in Adam and Eve’s Garden of Eden.

“All these hidden biblical images are related to a secret message left by the artist. They represent the allegories of the Genesis and New Testament and open the doors to a new way of reading these artworks,” Conti said.

According to Conti, Leonardo da Vinci and other Renaissance artists had knowledge of the allegories mentioned in many biblical references and in the treaties of Philo of Alexandria, a 1st century philosopher and theologian.

“All the images are related to explanations given by Philo, who reveals that the Bible is a symbolic representation of the history of the human intelligence,” Conti said. “Adam is the intelligence that resides in the mind of every human, while Eve is the corporal sensibility. The hidden images in the paintings tell this story and can only be seen with a mirror by those with sharp vision.”

He claims that clear references to the language of mirrors also exist in the book “Lives of the Artists” by Giorgio Vasari, the 16th century painter and art historian.

Nevertheless, the theory has raised skepticism in Italy.

While the Vatican commented that the study required “solid proof” and needed to be supported by art critics, the daily Il Giornale dismissed the claim as “pareidolia,” a psychological phenomenon.

“Our brain tries to give a coherent meaning when faced with ambiguous figures, such as when we look at the clouds in the sky,” Joseph Thornborn wrote in Il Giornale. “If we apply the mirror technique to a picture of Marilyn Monroe, we obtain a disquieting face with a chalice. Right, there is the Holy Grail on Marilyn’s forehead.”