How to say “Maya's hiding behind the puppet theater, so let's act surprised when she pops out.” in Japanese

In Japanese

マヤが人形劇(にんぎょうげき)の舞台(ぶたい)の後(うし)ろに隠(かく)れてるから、出(で)てきたらびっくりしたふりしよう。

Maya ga ningyougeki no butai no ushiro ni kakureteru kara, dete kitara bikkuri shita furi shiyou.