Tom offers to talk to Matthew to see why he and Mary are fighting, while Anna tries to convince Mary to forgive Matthew. (Anna spouts a Dowager worthy-line here. "What I see is a good man m'lady. And they're not like buses. There won't be another one 'round in ten minutes time.")
To Mary's credit, she says it's not about the money -- rather Matthew's reluctance to help the family if he could.
Thank goodness for Tom, who becomes the voice of all Matthew and Mary 'shippers when he speaks to Matthew. "But you're meant to be together. I've known that as long as I've been at the house. And at first this kept you apart, then that kept you apart. But please don't risk it a third time. Because I'll tell you this. You won't be happy with anyone else as long as Lady Mary walks the Earth."
Branson's speech inspires Matthew to sneak into Downton to see Mary. With the door in between them, he repeats Branson's words about never being happy with anyone else, and they share a sweet, yet intimate kiss with their eyes closed, although Mary cheats a bit. The wedding is back on.
The morning of the wedding, Robert thanks Tom for fixing everything, and the pair come to somewhat of a truce about their relationship. Meanwhile, Lady Grantham tries to give her daughter some wedding night advice, but Mary says she really doesn't need it. (Mom, remember the time I had sex with the Turkish gentleman?)
The three Crawley sisters and the mother share a private moment together. Sybil is sweet, "I know mine was a wild runaway marriage, darling. And yours is the one that everyone wanted. What's so thrilling is that this is every bit as romantic." Edith is nasty, "Love and position in one handsome package, who could ask for more?" And Cora is motherly. "Never mind, Edith. Well, very, very good luck my beautiful daughter."
Mary then descends the stairs, wearing a gorgeous dress as Robert and Carson watch admiringly. We get a nice father-daughter moment when Robert tells Mary, "I'm so very very happy, I feel my chest will explode."
And so, Robert escorts Mary down the aisle, and she teases Matthew about not showing up. But they do tie the knot.
NEXT: Unfortunately, we don't get to witness the wedding night...