Regan is a twelve-year-old student at a specialized time-travel Academy. She struggles to memorize historical facts and keep up with her reading, but she possesses strong intuition for identifying disguised time-travelers. Living in the commander's house rather than the dorms, she feels isolated from her peers and burdened by her mother's high expectations.

Elliot is a highly ambitious twelve-year-old orphan who ranks at the top of his class at the Academy. He values rules and academic perfection, utilizing his encyclopedic knowledge of history to excel in simulations. Lacking a family, he finds his identity in being the best and hopes to become commander-in-chief one day to secure a comfortable life.

Commander Fitz serves as the first female commander-in-chief of the Academy. She is an accomplished and serious leader who expects excellence from her students, especially her daughter. While she maintains a strict professional demeanor, she also tries to offer support and encouragement to Regan during difficult training exercises.

Officer Salzburg is a security professional at the Academy who can no longer time travel due to the physical toll of early equipment. He focuses heavily on campus safety and advocates for installing new camera technology to detect temporal anomalies. He maintains a friendly but professional relationship with the Academy's leadership.

Professor Callaway runs the secretive Lewis & Clark partner program on an isolated island. He adopts a jovial, slightly eccentric teaching style that emphasizes adaptability over rigid preparation. He firmly believes in the power of teamwork, intentionally pairing students whose opposing traits complement each other.

Sam is a recent graduate of the Lewis & Clark program who now works on active duty while continuing to live in the mountain facility. He takes his responsibilities seriously and exhibits an intense focus when training new recruits. He acts as a mentor figure, helping younger students adjust to the cooperative environment.

Serina is the other half of the first graduating pair from the Lewis & Clark program. She presents a warm and welcoming attitude toward new students, balancing her brother's more intense demeanor. She actively helps newcomers settle into the dorms and explains the daily routines of the mountain facility.

Tess is a student training in the Lewis & Clark partner program. She lives in the mountain facility and approaches her education with a friendly, helpful attitude. She easily navigates the unconventional rules of the secret program and helps orient new students.

Eliana is a student in the Lewis & Clark partner program who trains closely with her cousin. She strongly resembles Tess, making it difficult for newcomers to tell them apart. She is dedicated to her training and integrates well into the group environment.

Corban is a student in the Lewis & Clark program who proves that biological relation is not necessary for a successful partnership. He possesses a friendly disposition and actively encourages new students to socialize with the rest of the small group.

Blake is a student at the secretive Lewis & Clark branch of the Academy. Working alongside Corban, he demonstrates the effectiveness of the program's cooperative training model.

Professor Green is an instructor at the main Academy. He emphasizes the importance of building character rather than simply relying on intelligence, attempting to teach his students moral responsibility through menial tasks.

Professor Treebaun is a grumpy instructor at the Academy who reviews students' mistakes after their practice runs. He facilitates the process of analyzing the catastrophic historical consequences of small errors.

Agent Chris is an active adult time-traveler who becomes stranded in 1911 New York during an emergency. She requires immediate rescue while attempting to apprehend a criminal in a burning building.

Professor O'Reilly teaches the "Nuance and Observation" class at the Lewis & Clark program. He uses practical, visual exercises to train students in spotting historical inaccuracies.

Professor Tramble is a faculty member at the Lewis & Clark facility who assists with the technical and medical aspects of time travel, ensuring students have the proper equipment for dangerous environments.