Travis Kelce, a lifelong theme-park superfan, said his goal is to make Six Flags special for the next generation|killatrav|Instagram

Six Flags’ stock jumped 18% Tuesday after activist hedge fund Jana Partners and NFL star Travis Kelce revealed a 9% stake worth about $200 million in the struggling theme park operator. 

Jana managing partner Scott Ostfeld announced the move at an investor summit, saying they aim to revamp marketing, upgrade technology, and possibly explore a sale to boost Six Flags’ $2.6 billion market value.

Kelce, a lifelong theme-park superfan, said his goal is to make Six Flags special for the next generation. His celebrity appeal, boosted by his relationship with pop star Taylor Swift, is expected to help reenergize the brand and attract visitors.

Six Flags shares had plunged nearly 50% year-to-date due to bad weather and declining attendance. Leadership shake-ups are ongoing, with CEO Richard Zimmerman and several top executives set to exit by year’s end.