In a Macusa/MoM joint ball/conference (or somekind of gathering for original 12 & Sacred 28, or any other situation preferred). Leta and some other self-important purebloods find Newt in there and go mock him and try to make fun of him, and since now Newt's book was published and become the most famous Magizoologist in the world, they decide that Newt can become Leta's play toy / pet again. Only then Director Graves, the man (with his look, his position in MACUSA and his family) that every single woman and man in the room dream about, come and rescue his newly married beloved husband

bonus if Leta actually do like Newt (secretly) and genuinely mean it of that mocking suggestion. But well, just as Quennie said, she is a taker, and Newt needs a giver. (and Do you think Percival will ever let go of his precious cinnamon roll? don't be a silly girl)