Included here is basic information about Marcus Isaacson and Lucius Isaacson from the Alienist books. For the Isaacson brothers’ character analysis, quotes made by the Isaacson brothers, or character testimonials about the Isaacson brothers, please use the side menu.

The Isaacsons

Marcus & Lucius Isaacson Basic Information


Names: Detective Sergeants Marcus Isaacson & Lucius Isaacson
Birth Date: Estimated the 1860s
Birth Place: New York, NY
Appearance: The Alienist, 72-3:

Standing by the tables were two men, both wearing three-piece wool suits, the taller man’s a subdued but fashionably checked pattern, the shorter’s simple black. […] As [the taller man] leaned into the bright light around the table I would see that his Semitic features were quite handsome — strong nose, steady brown eyes, and a good head of curling hair. The shorter man, by contrast, had small eyes, a fleshy face that was beaded with sweat, and thinning hair. They both looked to be in their early thirties.

Parents & Siblings

Parents: Jewish immigrants from Europe. The mother appears to speak a Germanic language.
Siblings: Other than each other, they have one younger sister named Cordelia.

Working Life

Education: Marcus trained to be a lawyer and Lucius trained to be a doctor. They both have training in criminal science and forensic medicine.
Occupation and Places of Work: After initially doing work for the Pinkerton National Detective Agency, they went on to join the police force. They work as Detective Sergeants and have their offices at the Police Department Headquarters on Mulberry Street.

Private Life

Status: Bachelors.
Home: Live with their parents. Their home is located on Second Street between First Avenue and Second Avenue.
Transportation: No private transportation. They walk or use cabs (hansoms) instead.
Past/Present Servants: Unknown.
Friends/Associates: Theodore Roosevelt, Laszlo Kreizler, Sara Howard, John Moore, Alexander Macleod.
Past/Present Love Interests: Unknown.

— Last updated on by Kim