mastermind
n. countablen. a person who plans and directs a very complex or difficult project. People often use this word for someone who is extremely clever at organizing things, sometimes for a crime.
n. a person who originates, directs, or takes responsibility for a highly complex or ingenious plan or project. Often carries a connotation of exceptional intelligence or strategic foresight.
She was the mastermind behind the successful marketing campaign.
Police are still searching for the mastermind who organized the elaborate bank robbery last month.
While many contributed to the architectural design, it was the lead engineer who acted as the mastermind, coordinating the structural, aesthetic, and environmental requirements into a single cohesive vision.
From master + mind.
Frequently used in the phrase 'the mastermind behind' followed by a noun phrase.