Complex sentence: Frustrated by his inability to fight the reaper, Bannister attempts to commit temporary suicide so he can stop the reaper's killing spree, with Lynskey helping Bannister to go into suspended animation by using specialized drugs to temporarily stop his heart.
Split into simpler sentences: Frustrated by his inability to fight the reaper, Bannister attempts to commit suicide so he can stop the reaper's killing spree. However, Lynskey helps Bannister to instead go into suspended animation, using specialized drugs to temporarily stop his heart.