I Know What You Did Last Summer

The name of this movie is I Know What You Did Last Summer released in 1997-10-17 and it's main theme is As they celebrate their high school graduation, four friends are involved in a hit-and-run accident when their car hits and apparently kills a pedestrian on an isolated roadway. They dispose of the body and vow to keep the incident a secret, a year later somebody starts sending them letters bearing the warning I Know What You Did Last Summer..