Who is the man in black from the 39 clues?

Answer 1

The Man In Black is Grace and Beatrice Cahill's brother. He disappeared for 50 years and his identity is found out in Storm Warning. He is a Madrigal and is said to have many similar traits to Amy and Dan.

Answer 2

The Man in Black is a mysterious and enigmatic figure who appears throughout The 39 Clues series. He is affiliated with the Vespers and plays a significant role in the hunt for the clues. His true identity and motives are not fully revealed until later in the series.

Answer 3

Fiske Cahill, he is Grace's brother.