Perseus "Percy" Jackson is a fictional character in Rick Riordan's Olympian Demigod series, appearing as the title character and narrator in the first series, Percy Jackson & the Olympians, and a protagonist in the second series, The Heroes of Olympus. At the start of the first series, Percy is introduced as a troubled twelve-year-old diagnosed with both ADHD and dyslexia. After the Furies attack him at school, Grover, a satyr, escorts him to Camp Half-Blood, a secret camp built to train and protect Greek demigods. At camp, Percy learns that his father is Poseidon, the god of the sea, and is thus a child mentioned in the Great Prophecy, a prophecy that was given by the Oracle seventy years before the start of the series. Throughout the series, Percy embarks on several quests to save his friends and the Olympian gods of Mount Olympus.

The second book, The Sea of Monsters, explains that Percy's mother named him after Perseus because he was one of the few heroes that had a happy ending. In the original myth, Perseus is the son of Zeus, not Poseidon, as Percy is. Riordan did this because he thought it was "too obvious" because "everybody's always the son of Zeus...because he's the big guy". He thought it would be more "interesting" for the main hero to be the son of the second-biggest god, which would make Percy have to try "a little bit harder". As for Percy's surname, Jackson, Riordan stated that it was a name he had been "always very fond of". As a teacher, he had taught about Andrew Jackson and Stonewall Jackson in his America history classes, his grandfather's nickname was Jack, and the main character in his Tres Navarre series is Jackson. He decided that it "sounded good" with Percy.

Richard Russell "Rick" Riordan (/ˈraɪərˌdɛn/), Jr. (born June 5, 1964) is an American author best known for writing the Percy Jackson & the Olympians series. He also wrote the Tres Navarre mystery series for adults and helped to edit Demigods and Monsters, a collection of essays on the topic of his Percy Jackson series. He helped develop the ten books in The 39 Clues series, published by Scholastic Corporation, and wrote the first book in the series, The Maze of Bones. He recently completed a trilogy that focuses on Egyptian mythology, The Kane Chronicles, and is working on The Heroes of Olympus, which is the sequel to the Percy Jackson series and focuses on Greek and Roman mythology.

Rick was raised in Texas. He graduated from Alamo Heights High School in 1982 and the University of Texas at Austin in 1986, where he double-majored in English and Social Studies. Riordan taught English and Social Studies in Presidio Hill School in San Francisco for eight years. He was awarded St. Mary's Hall's first Master Teacher Award in 2002.

Logan Wade Lerman (born January 19, 1992) is an American actor, known for playing the title role in the 2010 fantasy-adventure Percy Jackson & the Olympians: The Lightning Thief. He appeared in commercials in the mid 1990s, before starring in the series Jack & Bobby (2004–2005) and the movies The Butterfly Effect (2004) and Hoot (2006). Lerman gained further recognition for his roles in the western 3:10 to Yuma, the thriller The Number 23, the comedy Meet Bill, and 2009's Gamer and My One and Only. He played d'Artagnan in 2011's The Three Musketeers, and will star in an adaptation of the novel The Perks of Being a Wallflower.

Lerman was born in Beverly Hills, California. His mother, Lisa (née Goldman), works as his manager, and his father, Larry Lerman, is a businessman and orthotist. He has two siblings, Lindsey and Lucas, both older. Logan and his family are Jewish. Most of his relatives work in the medical profession. His family owns and operates the orthotics and prosthetics company Lerman & Son, which is managed by his paternal grandparents, Mina (Schwartz) and Max Lerman, and had been founded by his great-grandfather, Jacob Lerman, in 1915. Logan's family had left Europe in the 1930s, because of the Nazi regime, and settled in California in the 1940s.