The club says they've signed the versatile Mann – who can cover hooker, fullback, centre, five-eighth and lock – with a view of further development as a hooker.

"We identified Kurt as a player of interest quite some time ago," coach Nathan Brown said today. "We believe Kurt has the potential to become a hooker and his ability to play a range of positions is an added bonus in today's game.

"Kurt expressed a desire to secure a regular position and he'll be given every opportunity to do that."

Mann returns to the Knights after six years away from the Hunter. Although a Queensland product, Mann started with the Knights straight out of high school in the SG Ball Premiership team in 2011.

Knights Player List Manager Troy Pezet said Mann's homecoming is yet another key addition to the club's roster.

"Kurt is a terrific player and quality person," Pezet said. "He also brings a lot of winning experience with him. He's played 88 NRL games and scored 30 tries over his career."

The 25-year-old played SG Ball and 20s for the Knights in 2011 and 2012 before heading to Melbourne where he made his NRL debut in 2014.

After three seasons with the Storm across the 20s and first grade, Mann moved to St George Illawarra where he's spent the last three seasons.

"I'm really excited to return to the club," Mann said. "It all began for me in Newy. I left Queensland as a young kid and was fortunate enough to play SG Ball and 20s for the Knights.

"It's a homecoming of sorts. I can't wait to meet everyone and get to work."

Mann's deal with the Knights will keep him on contract until at least the end of 2021.