There's still some controversy about this one. What we can say for certain - because both sides have confirmed it - is that Luke Grimes walked away from 'True Blood' at around the same time that he found out his character was due to have a same-sex relationship with another character played by Nelsan Ellis. What the parties disagree on is why that happened.
Grimes says that it was all down to a schedule conflict, and that a movie part he'd accepted meant he could no longer commit to 'True Blood.' Nelsan says that Grimes never said anything about any movie parts until he found out his character was going to be involved in gay scenes, and then the 'movie role' appeared out of nowhere. Nelsan was less than impressed by Grimes' attitude, and says that he can't understand why anyone would give up a job that paid big money just because they couldn't stomach a few gay kisses.