Complex sentence: In the initial draft, the love story was between a heterosexual couple, but Brooker changed it because he thought this gave the episode an extra resonance, as same-sex marriage was not legal in 1987.
Split into simpler sentences: In the initial draft, the love story was between a heterosexual couple, but Brooker changed it. He revealed that he thought this gave the episode an extra resonance, because same-sex marriage was not legal in 1987.