Double Rugby World Cup-winning scrumhalf Cobus Reinach will boost the Stormers squad when he joins the fold ahead of the 2025-26 season.
The experienced Reinach, who has 39 Springboks caps, will make his return to South Africa at the end of the current season, having played in England and France for the last seven years.
"Cobus has proven himself a threat at the highest level of the game and we are expecting him to fit in seamlessly here," Stormers Director of Rugby John Dobson said.
"He is a double World Cup winner and his considerable experience will be vital as we develop the next generation of young talent, with the likes of Imad Khan and Asad Moos set to benefit greatly from working closely with him.
"His attacking abilities are well-known, but he is also a player with great rugby IQ, and given his knowledge of European conditions and opposition he will provide plenty of value on and off the pitch."
Known for his explosive pace and pinpoint delivery, Reinach also brings a wealth of experience in European conditions with him to Cape Town.
"It will obviously be great for my family and I to return home, but what is just as exciting for me is to join a team playing such a great brand of rugby," Reinach said.
"I know a lot of the Stormers players well and I feel that I have a lot to offer within their game model, so I am looking forward to connecting with my new teammates and coaches when I move down to Cape Town at the end of the season."
Stormers Rugby CEO Johan le Roux said that attracting the interest of a top player like Reinach shows that the project is moving in the right direction.
"Cobus is a premier talent and we are thrilled to have someone of his quality coming in to bolster our squad," le Roux said.
"While the primary focus will always be on developing local talent, it is also important that our coaching staff are on the look-out for strategic acquisitions at the top end of the game that will help take us forward."