Complex sentence: The interior of the Paris Opera House was recreated on an epic scale for the film, and remains the longest-standing film-set to this day, being used for the 1943 remake with Claude Rains, as well as numerous non-horror pictures.
Split into simpler sentences: The interior of the Paris Opera House was recreated on an epic scale for the film, and remains the longest-standing film-set to this day. It was used for the 1943 remake with Claude Rains, as well as numerous non-horror pictures.