The study looked at how stock index futures in China affect the prices of the actual stock market. They found that the futures market has a big influence on price discovery, especially after a regulation change in 2015. The CSI 500 index futures play a key role in setting prices, and a crash in these futures could lead to a market-wide crisis. This could explain the market crash in 2015. The research gives us new insights into how futures trading impacts the Chinese stock market.