Avid fans of The Walking Dead comics know that now is the time in the story line to introduce pivotal character Tyreese into the TV series. And so they will. Chad Coleman (The Wire) has been confirmed to play Tyreese. He could appear as early as the December 2nd episode of the series.
In the comics, Tyreese is an important character, one who acts as Rick's second-in-command and is romantically linked to both Carol and Michonne. As is the nature with The Walking Dead, details on TV-Tyreese's role is vague, but TVOverMind.com says that he will spend the majority of the season in Woodbury.