Complex sentence: As casting isn't to start for quite a while the pair hire her as their secretary/receunwanted success of Springtime for Hitler, she and Leo flee to Rio de Janeiro where they marry.
Split into simpler sentences: As casting isn't to start for quite a while the pair hire her as their secretary/receptionist. Before this, after the unwanted success of Springtime for Hitler, she and Leo flee to Rio de Janeiro where they marry.