1In a medium bowl, combine crackers, butter and sugar. Press mixture into bottom and sides of a 9x13 inch pan.
2In a large bowl, combine whipped topping, pudding and sour cream; whisk together. Put half of this mixture into crust. Layer sliced bananas over top of pie. Pour second half of pudding mixture over top of bananas.
3Immediately cover and refrigerate pie for one hour.