Complex sentence: During a one-year hiatus, Edington groomed Kent for what he intended to be a high-profile career, however by the time she returned to films, her popularity had waned and she was unable to establish herself again.
Split into simpler sentences: During a one-year hiatus, Edington groomed Kent for what he intended to be a high-profile career. By the time she returned to films, however, her popularity had waned and she was unable to establish herself again.