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Warning! This page contains spoilers for The Sword of Summer.
Dr. Frederick Chase is the mortal father of Greek demigod, Annabeth Chase, and her half brothers, Bobby Chase and Matthew Chase, the husband to Mrs. Chase, brother of Randolph Chase (and his late sister), and the uncle of Magnus Chase.
When Frederick Chase was young, he was a brilliant man who wanted to go to college, but he didn't have enough money. His brilliance and wit gained the attention of Athena, the goddess of wisdom. She helped him get into Harvard University and he finished his studies successfully with her help. Their relationship eventually ended on good terms and Athena sent him their daughter, Annabeth Chase. She appeared on Frederick's doorstep in a golden cradle carried down from Olympus by Zephyros, the West Wind. She was considered a "brain child" like all other children of Athena, which means that they were born from the thoughts of the goddess, which makes them the only demigods to be claimed at birth. Frederick originally wanted Athena to take Annabeth back, but she sternly told him that demigods must be raised by their mortal parent.
Frederick then subsequently married an Asian woman and they had two sons: Bobby and Matthew. Dr. Chase's family was frequently attacked by monsters, due to Annabeth being a demigod. Annabeth eventually thought that her mortal family resented her for this, and eventually ran away. She later made it to Camp Half-Blood with the help of Thalia Grace, Luke Castellan, and Grover Underwood. From camp, Annabeth would talk to her father mostly in letter form, as phones were too dangerous for a demigod. Mr. Chase would occasionally ask her to return home, but Annabeth always refused.
Annabeth eventually returned home at her father's request, but left when she saw that nothing had changed. Her father then sent her his college ring in hopes that she would remember him by it, and be convinced to come home. She started to wear his college ring on her necklace with the beads that she earned every year at Camp Half-Blood.
Dr. Chase and his family were seen by Percy at the end of the summer when Annabeth decided to go home for the school year.
Annabeth accompanied Percy Jackson and Thalia Grace to assist Grover with two new demigods at a military school. Annabeth told Percy that her father was moving to San Francisco, but she was unsure whether to go because the area contained the Titan base, therefore thriving with monsters. Annabeth, during the mission, went missing and Percy went on a quest to save Lady Artemis to find her.
In San Francisco, Thalia suggested they visit Frederick Chase for transportation. The revelation of his daughter's disappearance shocked Dr. Chase who agreed to give the questers his car which they unintentionally destroyed. After rescuing Artemis, the group were gravely endangered by a fleet of monsters, but Dr. Chase, ignoring the warnings given to stay away, flew in on his plane, a Sopwith Camel. Using special bullets he created out of some of Annabeth's Celestial Bronze weapons, he shot and destroyed several monsters, ensuring the others would escape.
Dr. Chase was relieved that his daughter was safe and reminded her she still had a home with him just before Annabeth left with Percy and Thalia on pegasi.
Annabeth remembers the time she used to hate her mortal family, and says it was dumb of her to think that way for so long. Then she remembered her uncle and cousin living in Boston that she never saw due to her father and uncle not getting along.
Ten years later, Fredrick and Annabeth, are looking for his sister's son Magnus after being contacted by Randolph that Magnus has been missing for two years since his mother died.
Frederick Chase is a fairly normal mortal, though with a genius-level intellect. His genius caught the eye of Athena, who was enchanted by his wisdom. He most likely caught her attention by his fascination with wars and his love for airplanes. Frederick loves Annabeth very much, though he did not want her at first, but that is somewhat expected, since he didn't know that his friendship with Athena would result in a brain child, and when she came, he did not have time to take care of her, as he was not originally prepared. Despite this, he has attempted to be on good terms with his daughter. When she ran away at seven, Frederick was heartbroken until her return several years later. Percy once described Dr. Chase as an "excellent mad scientist" because of his experiment with celestial bronze bullets.
Frederick is described as a handsome, athletic, middle-aged man with sandy-colored hair like his daughter Annabeth Chase, and intense brown eyes.
Frederick's twins sons with his wife Mrs. Chase.
Frederick's wife, and Bobby and Matthew's mother. She is the step mother of Annabeth. She married Frederick, when Annabeth was five. He loves his wife very much.
Frederick's daughter with Athena goddess of wisdom, warfare and crafts. He was surprised that he had an infant daughter to care for, and tried to get Athena to take her back, but she sternly told him that demigods must be raised by their mortal parent. His family was attacked by monsters due to Annabeth being a demigod. Annabeth eventually thought that her mortal family resented her for this, and ran away. In The Titan's Curse, it seems her relationship with them is getting better, and by The Last Olympian she seems to be living with them again (though, this is not for certain because she is going to go to a school in New York near Percy's, and her family lives in San Francisco).
His brilliance and wit drew the attention of Athena. She helped him get into college, and he finished his studies successfully with her help. Their relationship eventually ended on good terms.
- When the Sirens sang to Annabeth, she saw her father and her mother, Athena, together again, and happy. She saw Luke sitting next to them, patting the ground next to him, asking her to stay.
- Frederick is a professor at West Point and teaches American history.
- Frederick "plays with toy soldiers" according to Percy. In other words, he makes models of WWI battles. Although, he is said to play with them, making the shooting and explosion sound effects and other things along the line of that.
- Dr. Chase also appears to be able to see through the Mist. While on Mt. Tam, he successfully shot Luke's monster army with his modified bullets without harming the demigods. He also saw Blackjack, Guido and Porkpie without any difficulty and questioned how the Pegasi could fly with their body mass v.s. wing span ratio.
- He is the only mortal parent of the Seven that is both alive and has not been captured.
- His favorite movie is Roman Holiday.
- As being a professor in American and Military History, he is interested in collecting war souvenirs such as his Sopwith Camel biplanes from World War I.