Dan Brown's third novel in the Robert Langdon series, after Angel & Demons and The Da Vinci Code.

The Lost Symbol revolves around the secret fraternity known as the Freemasons, guardians of a legendary treasure, the Ancient Mysteries whose location is inscribed on the Masonic Pyramid, hidden somewhere in Washington DC.
Robert Langdon once again finds himself involved in a centuries-old quest to find the Lost Word, which will  guide mankind from darkness to enlightenment.

Ancient secrets, a brotherhood, a murderous madman, enigmatic messages, allegories on historical objects & landmarks - sounds familiar, right?
Yes, it has almost the same storyline as the previous two books, but you just don't care. The endless thrills & incredible plot twists make it yet another classic Dan Brown book.

Even though The Da Vinci code had set the bar very high, the fact is that The Lost Symbol has exceeded all expectations. Despite the fast pace of the action, Dan Brown never refrains from providing meticulous descriptions of the surroundings. The fictitious parts are so seamlessly intertwined with the facts that the uninitiated won't be able to distinguish one from the other.
Once again, Dan Brown shows his proficiency at devising cryptic riddles & deriving extraordinary revelations from mundane objects or famous relics.

From start to finish, the reader's emotions alternate between excitement, apprehension, anticipation & finally mesmerisation. The Lost Symbol is a rollercoaster ride which you wish will never stop (& it doesn’t).  This book confirms beyond doubt Dan Brown's prowess at writing breathtaking stories.
The Lost Symbol is a true page-turner & it may well become one of the best-selling novels ever.

The Facts & Fiction

Spoiler Warning: Henceforth, this post contains plot spoilers. If you haven't read the book yet, stop reading right now. ;)

Washington DC

The cornerstone of the story is Washington DC, scattered with Masonic monuments built by the Founding Fathers. I'd suggest a quick look on Wikipedia or Google Maps to be more acquainted with the landmarks.
It's definitely no coincidence that the roads were drawn exactly like the Masonic compass & the square...
& if you’re looking for images of all the landmarks, check out this Flickr set – The Lost Symbol.

Liquid Breathing 
When it comes to writing plot twists, no one can surpass Dan Brown. In The Lost Symbol, the masterstroke was the drowning of Robert Langdon & then his revival. I was really convinced that Langdon had died until it was revealed that it was a liquid breathing tank.
Of course, such commercial liquid breathing tanks do not exist. Liquid breathing is highly experimental & is only used for diving & medical treatment. :)

Pop Culture
A website – http://www.theintentionexperiment.com
A blog - Future Applications in Computational Metasystem Analysis
& even Twitter… :P

Technology is linking us in ways we never imagined possible: Twitter, Google, Wikipedia, and others—all blend to create a web of interconnected minds.” She laughed. “And I guarantee you, as soon as I publish my work, the Twitterati will all be sending tweets that say, ‘learning about Noetics,’ and interest in this science will explode exponentially.”

Langdon’s eyelids felt impossibly heavy. “You know, I still haven’t learned how to send a twitter.”

“A tweet,” she corrected, laughing.

& there was also an iPhone, considered too user-unfriendly & was eventually crushed. ;)

Noetic Science & Random Number Generators
Our brain is much more powerful than we can imagine, but is it powerful enough to affect our surroundings. In the book, Katherine Solomon scientifically demonstrates the power of the mind over matter.
While rationally, such occurrences are impossible, we can't ignore them either. Psychic phenomena has been demonstrated & there is no logical explanation for the behaviour of the random number generators before 9/11 happened (although they could have been tampered with). Clearly more research is required.
Correlations of continuous random data with major world events (pdf)

Sir Isaac Newton
In all three books, Angels & Demons, The Da Vinci Code & The Lost Symbol, a major recurrent figure is Sir Isaac Newton (or Jeova Sanctus Unus), respectively as an Illuminatus, the Grand Master of the Priory of Sion & a Freemason (& Rosicrucian & inventor of the Newton Scale). 
Who bets that Newton will appear once again in a fourth novel? :)

21g
When I first started reading about Katherine Solomon’s research on weighing the human soul, I was almost expecting this figure to appear. Thankfully Dan Brown didn’t reveal anything, because 21 grams is supposedly the weight of a human soul. Actually, it’s an urban myth originating from Dr. Duncan MacDougall.

The Scriptures
I was expecting a more startling revelation than the Ancient Mysteries being the Scriptures - the Bible, the Vedas, the Quran, etc.
All those efforts only to find out that The Last Word is the Bible? An ending like in National Treasure would have been perfect.
Coming back to the Scriptures, everyone can have their own interpretation of the teachings & derive meanings that suit their objectives. While we still have a lot to learn from them, I doubt they can explain the workings of the universe. ;)

Kryptos

The undecipherable art piece exposed at the CIA was mentioned on the cover of The Da Vinci Code. Although it’s appearance in The Lost Symbol is pretty insignificant – the Kryptos is another map leading to the Ancient Mysteries.

Freemasons in Mauritius

The plot revolves around Freemasonry, where it's revealed that most Masons count among the most affluent & powerful persons. I've always been fascinated by the Freemasons, ever since I heard that they were a secret society.
What do we actually know about Freemasonry in Mauritius? (apart from the rumours that SSR was a Freemason).

Freemasonry was brought in by the French in 1765 & had famous members like the first Governor of Mauritius, Robert Farquhar. The Grand Lodge of Mauritius was constituted on 12th March 2005.
The main role of Freemasonry is philanthropy. Apart from that, we don't know much about their secret initiation ceremonies. The identities of the members are also hidden, but it’s known that they are affluent & hold influential positions. 
Contrary to what conspiracy theorists affirm, I do not think that Freemasons hold the reins of this country. :)

Here are a few articles on franc-maçonnerie from L’Express:
- Jacques Sadreux "Il y a, à la Rose-Croix, une représentation sociologique parfaite" - 21/10/2010
- Serge Toussaint , "Un frère rosicrucien est avant tout un humaniste" - 15/03/2010
- Pierre Notton: “L’Eglise semble avoir oublié cette proximité historique qu’elle avait avec les francs-maçons” – 05/09/2009
- Pierre Lambicchi: “Le creuset de la franc-maçonnerie à Maurice est très fertile” – 22/12/2008
- Franc-maçonnerie: la Loge de la Triple Espérance célèbre son 230ème anniversaire – 19/12/2008
- Maçons frères de l’ombre – 04/07/2008
- La franc-maçonnerie plus transparente – 24/03/2008
- La voie intérieure – 20/05/2005
- La Franc-maçonnerie réaffirme sa présence – 19/03/2005
- Des franc-maçonnes lèvent le voile – 17/11/2004
- Chronique: La Triple Espérance de vie de la doyenne de nos Loges maçonniques – 01/12/2003
- Chronique: La franc-maçonnerie au rendez-vous des transitions révolutionnaires et anglaises (II) – 08/12/2003
- Chronique: La Triple Espérance coincée entre francophiles et anglophiles (III) – 15/12/2003
- Chronique: La Triple Espérance face aux résistances catholiques et britanniques (IV) – 22/12/2003
- Chronique: De la Triple Espérance à la Belle au Bois-Dormant (V) – 29/12/2003
- Chronique: La Triple Espérance aujourd’hui, demain et à jamais – 05/01/2004

Other links:
- The Grand Lodge of Mauritius
- MQ Magazine: An island tale
- MQ Magazine: Mauritius takes a leap forward

P.S. I've looked for the book "La franc-maconnerie a l'ile Maurice" at the UoM library, but it was already lent out. :|

Related links:
@sjdvda also blogged on it - The Lost Symbol