Complex sentence: On May 9,1936, she attended a play in which a geisha attacks her lover with a large knife, after which she decided to threaten Ishida with a knife at their next meeting.
Split into simpler sentences: On May 9,1936, she attended a play in which a geisha attacks her lover with a large knife. After seeing this, Abe decided to threaten Ishida with a knife at their next meeting.