NH 8421 then TW 244 at Narita
Chicago → Tokyo → Seoul
Timetable, Tokyo time
18:38NH 8421 from Chicago at the gate
14:00TW 244 to Seoul leaves the gate
19 h 22 apart on the timetable, overnight
TW 244 leaves 19 h 22 after NH 8421 arrives on the timetable: more than half a day, so not a connection we count.