Final episode in this period drama written by Downton Abbey creator Julian Fellowes. Frank and Mary plan their wedding, but Lady Arabella is still determined to stop them going ahead with the marriage, and tries to persuade Mary that it would be in Frank's best interests to marry someone else. Sir Roger's son Louis struggles to cope with his new position in society, and proves just as self-destructive as his father, drinking to excess and hurling abuse at his dinner guests.