He said: “It was a tough decision to leave the NRL but I couldn’t refuse the contract offered by the Dragons.”
“The club has great ambitions for next year, the tenth season of the Dragons in the Super League, and it’s great to be back and to be a part of that.
“To play in the NRL is something I’ve always wanted to do since I started playing rugby but I also always dreamed to lift a trophy with the Dragons.
“I’m really proud to come back in my club.”
Coach Laurent Frayssinous said: “I’m really satisfied to sign Rémi Casty.
“He will bring us his on-field qualities and his leadership and charism both on and off the field.
“He played in one of the best team in the world this season and he will share his experience to the team.”