Writing under his name, Bosch has created the Secret Series, a pentalogy of novels that is based on the five senses:

• The Name of This Book Is Secret (2007) is based on smell,
• If You're Reading This, It's Too Late (2008) is based on sound,
• This Book Is Not Good for You (2009) is based on taste,
• This Isn't What It Looks Like (2010) is based on sight, and
• This Book Is Not Yet Titled (2011) is based on touch.

Characters

The characters' names were not be revealed by Bosch "for security reasons", as he puts it. Instead, he gives them pseudonyms as well:

Protagonists

• Cassandra - a 12-year-old "survivalist-in-training" who is well-known for her pointy ears (which are perfect emotion thermometers) as the Jester is one of her ancestors. She was found in front of Grandpa Larry's fire house and raised by her "mother". Max-Ernest helps her in finding her "real" ,or biological mother. Usually called Cass.
• Max-Ernest - a 12-year-old boy who has a terrible case of nonstop-talking, among other things. His parents are 'divorced' (you'll read about this), and he is extremely literal as well as logical. They are psychologist. Max-Ernest has a knack for codes, riddles, and things of that nature. He lacks in the comedy category (though, not always). In 'This Isn't What It Looks Like,' the author hints that he and Max-Earnest are one and the same.
• Yo-Yoji - a 12-year-old Japanese musician (guitar, originally violin), who has just moved to Cass's hometown. Is rather rebellious.
• Amber - Cass, Yo-Yoji, and Max-Ernest's classmate. She had a huge crush on Yo-Yoji. She's also the "true worshipper" of the Skelton Sisters. She was used by Ms.Mauvais and Dr.L .
• Lily Wei - Once kidnapped by Ms. Mauvais and Dr.L. She is the master of defense and the head of the Physical Defense lesson in Terces Society. She is also Yo-Yoji's violin teacher. She has a pen-and-needle-like-sword in her violin bow. Famous of the words given by her father: "To go forward you must go back"
• Benjamin Blake - a classmate of Cass who has synesthesia; later kidnapped by Ms. Mauvais-the entire story is found in the 1st book.
• Melanie - the "adoptive" mother of Cass. She found Cass outside the fire house when she and the 2 grandpas were talking about "why can't I have a child..." . They saw how much she did need one and gave the child to her.
• Grandpa Larry and Grandpa Wayne - once Cass' mom's lectures, they now serve as pretend grandfathers/supervisors.
• Pietro Bergamo - Twin brother of Dr.L, also has synesthesia. He is a key member of the Terces Society and a former magician.
• Owen - a member of the Terces society playing a double role as a hired hand of the Midnight Sun spa ; he later rescued Cass and Max-Ernest from Dr.L and Ms.Mauvais. He is a spy with uncountable diguises and accents. A former pilot, waiter, butler, truck driver, etc.
• The Jester - founder of the Terces Society; ancestor of Cass. Friend and rescuer of young Cabbage Face.
• Mr. Cabbage Face - a homunculus or a man-made man, he is 21 and a HALF (don't forget the HALF) inches tall, with a disformed body; pal of the Jester, he is attracted to the Sound Prism. Created by Lord Pharaoh and has a massive appetite of meat. He is also a cannibal (well not really a cannibal, cannibals eat others of the same species, and there are no others like Mr.Cabbage face but he does eat humans) and fits in Max-Ernest's bag. Died at Lord Pharoh's graveyard.

Antagonists

• Ms. Antoinette Mauvais - one of the two main antagonists of the story; tries to capture the plot device that each book is based upon. She is stunning on the outside, but has not avoided aging over the years. Is in the Masters of the Midnight Sun group. Alchemist.
• Luciano Bergamo (Dr. L) - A doctor in the Masters of the Midnight Sun group. He was captured by Ms. Mauvais, and therfore, turned, if you know what I mean. Twin brother of Pietro-also archnemesis.
• Senior Hugo - an evil chef who specializes in chocolate making; works with Ms. Mauvais and Luciano
• Lord Pharaoh - a Swiss doctor who became a master alchemist. Lord Pharaoh created the homunculus named Cabbage Face and he also started the Midnight Sun.

Pseudonymous Bosch's pen name was still successful for a full 3 years. His identity has since been revealed.

Bosch was widely believed to be Megan McDonald, Rick Riordan, Heinrich Hoffmann, Daniel Handler (a.k.a. Lemony Snicket), Graeme Williams, Pietro Bergamo (hence the initials PB), Jon Scieszka, Trenton Lee Stewart, or a woman named Edie Bilmann.

In late 2009, Copyright.gov revealed that the copyright for The Name of This Book is Secret was Raphael Simon, who used the pseudonym of Pseudonymous Bosch. Bosch has stated that he had previously worked as a writer for the Nickelodeon children's show Rocket Power. A man named Raphael Simon is credited with writing two Rocket Power episodes in 2001 and 2002.

Known information

Some other information has been revealed by Raphael Simon.

Simon originally started The Name of This Book Is Secret in elementary school for a program called "Writing Partners", which paired adults up with children. Its purpose was to improve each other's writing techniques.

While he was partnered up with a child named May, he didn't have anything to send to her, so he decided to write a novel to her. After lots of positive feedback from her, he kept adding larger installments until, much after the program, he had come up with a marvelous story.

However, no matter how hard he tried, he could not come up with a good title for it. Suddenly, he had a logical explanation for this: the title was secret. And since the name was secret, he would have to come up with a pen name, too.

This had been successful for years.

"The Secret" is a secret, of course, in which the entire Secret Series is based upon. It is said to be the formula of immortality.

Every a few hundred years, a "Secret Keeper" is chosen to know and keep The Secret in his/her head safely. In This Book Is Not Good for You, Cass is chosen to be the Secret Keeper.

The Secret was discovered by a court physician in Luxor, 1212 BC. Three days after his discovery, he was executed either because he refused to tell the Pharaoh the Secret, or he did tell, and the Secret made the Pharaoh angry, so the Pharaoh demanded he be executed. Before the court physician died, he wrote the Secret on a papyrus, and asked for the papyrus to be buried with him.

It was, in fact, buried with him until years later, when it was taken by tomb-raiders. Again, they died violent deaths. In the early 1800s, the papyrus was found, and taken to the Prague, where it was purchased by a curious antique dealer. He gave it to an Egyptologist for translation. The Egyptologist went mad, and the papyrus was never seen again.

The antique dealer spent the rest of his life searching for The Secret until he died, alone, because of a terrible flesh-eating virus.

In book 4, Cassandra receives a the papyrus in the mail from the past. The secret is written on it in hieroglyphics but alas, she cannot read it because it rapidly turns to dust