Jeffrey Dean Morgan | Negan
Negan is a part of the main cast and played a former antagonist for a good chunk of the series. He first appeared as the leader of the Saviors and used whatever resources he had on hand to blackmail other communities. In turn, he’d offer protection against the walkers, which was highly effective.
Eventually, Negan is taken prisoner by the members in the Alexandria Safe-Zone, and he’s held for more than seven years before making his escape. However, after being away for so long, the world around him changed so drastically that he voluntarily returned to Alexandria and his cell to be alone.