Complex sentence: On the other hand, Wingate struggled to keep up with the flood of scripts coming in, to the point where Warner Bros.' head of production Darryl Zanuck wrote him a letter imploring him to pick up the pace.
Split into simpler sentences: On the other hand, Wingate struggled to keep up with the flood of scripts coming in, to the point where Warner Bro. 's head of production Darryl Zanuck wrote him a letter imploring him to pick up the pace.