Spread the warmed hot fudge toping along the bottom of the pie crust. The sauce needs to be loose enough to pour in/spread out but not scalding hot. Place the crust in the fridge to chill and set the fudge.
In a large bowl, add the milk, butterscotch sauce and the pudding mix. Beat with an electric mixer until well combined; ~2 minutes. Next, fold in 4 ounces (or one-third) of the whipped topping.
Remove the crust from the fridge and spoon the pudding mixture into the pie shell spreading it out evenly.
Top the pie with the remaining whipped topping, sprinkle on the toffee chips and drizzle on some additional butterscotch topping.
Place in the fridge, uncovered for at least 6 hours to chill out. Once it is all set, slice and loosely cover the rest of the pie with a lid or plastic wrap.