Walking Dead creator Robert Kirkman, during an IMDb interview with Kevin Smith Smith, taped in advance for this year’s San Diego Comic-Con, confirmed the strong rumor regarding the 9th season of the hit series being star Andrew Lincoln’s last.
“It’s looking that way,” said Kirkman reluctantly, when asked by Smith if Lincoln was leaving. The departure of the Rick Grimes character of course, however it might wind up happening, marks a huge divergence from the comics where Rick still exists. “At the end of the day,” Kirkman explained, “it’s all about Andrew Lincoln. This is a human being. This is someone I have known for almost a decade, somebody that I love. He’s been sweating in Georgia, away from his family, for so long.”
Source: IGN.com The Walking Dead: Andrew Lincoln's Departure Confirmed