Avery is serving a life sentence for the 2005 killing of photographer Teresa Halbach, a case that became the focus of a popular Netflix series.
The new episodes will provide an in-depth look into Steven Avery and Brendan Dassey's post-conviction process.
"Thank you for believing in me," he wrote.
"I’m 1,000 percent confident that I’ll be free.”
A judge overturned Dassey’s conviction on Friday, saying his pivotal 2006 confession had been made involuntarily.
He'll be released within 90 days unless the state wants to retry him.
"Making A Murderer" isn't just a problem in Manitowoc, Wisconsin.