This is "A Man embracing a Woman" by Dosso Dossi. Commissioned in 1524 by Alfonso d'Este, Duke of Ferrara, for his castle in Ferrara, it was originally part of a circular painting on wood as a ceiling decoration.
The two figures, a woman and a man with his hand over her shoulder, lean over a parapet. The woman appears to be speaking or singing to the man beside her, whose blonde curls are crowned with a wreath of jasmine. The surviving fragment of her hand suggests she was perhaps about to drop something into our space below.
The figures were painted as if seen from below, giving them striking definition. Technical examination reveals that the ultramarine sky in Dosso's tondo was painted on top of another background, possibly of imaginary architecture. Unfortunately, all knowledge of the original meaning of the painting has been lost.
A Man embracing a Woman hangs in The National Gallery on Trafalgar Square, London — free to enter. Point your phone at any artwork there and audioguide.london plays a free audio guide in six languages — no app download needed.