Leonardo da Vinci (played by Tom Riley)
The first season found the genius inventor to be a cocky sort and one whose search for knowledge was almost artistic in its level of obsession, Riley says. "As a result, everyone around him would be collateral damage."
The next chapters in his life, however, find da Vinci's veering more toward the wise man of his later years and discovering that the negative influence he has on his friends is also a negative influence on himself.