The Da Vinci Code
Isaac Newton was a prominent historical figure in the novel as he not only was a Grand Master of the Priory of Sion but also his life holds the final clue in unveiling the hidden location of the Sangreal through unlocking the codex. Langdon and Sophie must research the final clue indirectly referencing Newton to discover what is missing from his tomb.
The Lost Symbol
Newton was believed to be a 33rd degree Freemason of the Scottish Rite after helping found the Ancient Grand Lodge of England in 1717. Katherine Solomon uses his Newton Temperature Scale to heat up the Masonic Pyramid to 33 degrees Newton which causes the capstone to glow with the writing "8 Franklin Square" as well as removes the wax sincera unveiling the 8X8 grid on the bottom of the pyramid. Additionally, the first magic square Langdon deciphered revealed the name of Isaac Newton in Latin which coincidentally was an anagram of Jeova Sanctus Unus, or One true God.