Complex sentence: Richard Sherman (Ewell), after sending his wife (Keyes) and son to Maine to escape the sweltering summer, meets the nameless model (Monroe), who is renting the apartment upstairs.
Split into simpler sentences: Richard Sherman (Ewell), sends his wife (Keyes) and son to Maine to escape the sweltering summer. He then meets the nameless model (Monroe), who is renting the apartment upstairs.