L3-37, known as Leo, is a runaway synth from the Institute in 2287.
Background[]
L3-37 was harbored and memory wiped by the Railroad. They have subsequently been trained to become a Railroad agent and assumed the name "Leo." The Institute has sent many coursers to bring them back, including X9-73, without success. The Institute's agents have last spotted Leo near the Corvega assembly plant in Lexington.[1]
Appearances[]
L3-37 is mentioned only in Fallout 4.
Behind the scenes[]
The designation "L3-37" is a gag reference, as it translates to "elite" in leetspeak, and appropriately describes a synth able to handle multiple coursers without trouble.