Complex sentence: Alfred Hitchcock described her performance as "rather mousy" and stated that it lacked animation, and said that it was only in the later films that she "really blossomed" and showed her true star quality.
Split into simpler sentences: Alfred Hitchcock described her performance as "rather mousy" and stated that it lacked animation. He said that it was only in her later films that she "really blossomed" and showed her true star quality.