The end of season seven saw Rick (played by Andrew) declare "All Out War" on the Saviors after months of torture.
Speaking at New York Comic-Con, Andrew, 44, revealed that his character has certainly changed since fans last saw him.
"I think he's ready for battle. I've always said that Rick is very much like a shark. He needs to keep moving, otherwise he dies," Andrew explained.
He added: "Giving him something to do with his grief and pain is essential. Kicking Negan's ass is as good a reason as any.
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Andrew Lincoln teased that Rick will die to get revenge on Negan
Rick will stop at nothing to kill Negan, even sacrificing his own life
"I think he's very focused. You saw him in the beginning of the scene last season on his knees, but he's a completely inverted Rick.
"He's a man who's willing to die. He's free for all intents and purposes," Andrew teased.
What's more, the actor admitted that Rick's actions in season eight made him "nervous" to go to work, something that he called "a testament to the writers".
"This is the payoff for last season, certainly in Rick's terms. The thing I love about the job after eight years and 100 episodes is that they keep pushing and pulling and hurting this man in new and unimaginable ways," he gushed.
Walking Dead Season 8: First Look
Wed, September 20, 2017
The Walking Dead's season eight premiere is a month away and new photos show the major characters preparing for the fight of their lives.
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This follows a rumour circulating that Rick will die in upcoming episodes.
After becoming the ultimate survivor, bosses have promised that the ultimate survivor "will die" at one point.
His son, Carl Grimes (Chandler Riggs) has been tipped to take on the lead role in his absence.
The Walking Dead returns to AMC on October 22 and will follow a day later on FOX UK. Seasons one to seven are currently available to watch on NOW TV.