To make the crust, mix together 2 cups of Oreo crumbs with melted butter.
Press crust into the bottom and up the sides of a 9 inch pie pan.
Place crust into freezer while you make the filling.
To make the filling, mix together the cream cheese, sugar and milk until smooth and creamy, about 2-3 minutes.
Divide the mixture evenly into two bowls (just under 1 cup of mixture per bowl).
Add the peanut butter to one bowl and mix until combined.
Add the cocoa and vanilla to the other bowl and mix until combined.
Add 4 ounces of Cool Whip to each bowl and lightly stir until combined.
Pour chocolate ice cream mixture into pie pan.
Sprinkle 1/2 cup Oreo crumbs evenly onto chocolate ice cream.
Top with peanut butter ice cream mixture.
Cover the top of the pie with chopped M&Ms and drizzle with chocolate sundae syrup.
Freeze until firm at least 8 to 12 hours.