Lemon Pie

1 (14 ounce) can sweetened condensed milk
1/2 cup lemon juice
1 (8 ounce) carton frozen whipped topping, thawed
1 - 9 inch graham cracker crust
                   
In a bowl, combine milk and lemon juice; mix until smooth
(mixture will begin to thicken). Fold in whipped topping;
spoon into crust. Chil until ready to serve.