Complex sentence: The film was an international hit, and along with "Confession" proved a breakthrough film for Anglo-Amalgamated who began making more expensive productions, often importing American stars to give them more international appeal.
Split into simpler sentences: The film was an international hit, and along with "Confession" proved a breakthrough for Anglo-Amalgamated. After its success the company began making more expensive productions, often importing American stars to give them more international appeal.