The Flash, Season 3

Iris:
What is all this?

Barry:
I've been really busy recently with trying to avoid the future, and I forgot that there's always another way.

Iris:
What is that?

Barry:
Making the future. [opens a box containing an antique engagement ring] Our future. [gets down on one knee] My great-grandfather gave this to my great-grandmother after World War Two. He wanted to propose before he was shipped out, but he didn't have the money. And he bought this three years later when he was stationed in London. Fought his way across France, all the way to Berlin, with this ring around his neck with his dog-tags. And when he got back, she was waiting for him in the dock of the Brooklyn Navy yards. He proposed on the spot. After my mom passed away, Joe held on to this for me. Until tonight.

Iris:
Barry...

Barry:
Iris West... will you marry me?