PLACE drink mix in large bowl. Add water; stir until mix is dissolved. Add ice cream. Beat with electric mixer on low speed until well blended. Gently stir in whipped topping. Freeze, if necessary, until mixture is thick enough to mound.

SPOON into crust.

FREEZE at least 4 hours or overnight until firm. Remove from freezer 15 min. before serving. Let stand at room temperature until pie can easily be cut. Store leftover pie in freezer.