[1] The painting shows a woman sitting on a large red chair in the balconies of the Paris Opéra House.

The rich colors of the painting draw the viewer in, deep shadows create contrast against the brightness of the light source.

Cassatt paints her sister up close, giving the viewer a place in the opera box next to Lydia.

Being a genre painter she was able to reproduce scenes of everyday life, domestic settings and parties, which she would romanticize to help create an ethereal air of wonder around the women she painted.

[4] "Glamour, fashionable costume, exquisitely tasteful settings served to create an idea that was understood to be intensely modern, a pale legacy of the poet".

The vast scene from Woman with a Pearl Necklace in a Loge isn't present here as the mirror is reflecting a dark room to the viewer.

Another painting in this oeuvre is In the Box, which was made in 1879; this depicts two women in balcony seats in a theater watching the performance unfold before them.

The background is handled in a very similar fashion with quick brushstrokes to convey the sense of other figures in the balcony seats across from them.

"Cassatt found a device for conjoining her fascination with the figure, notably of young women in smart day or evening clothes, with the need to situate them in a social setting-one of the ambiguous spaces of modernity which bourgeois femininity could occupy and contest.

[1] "Her work stood out in great contrast to the landscapes of Monet, Pissarro, and others, as well as the more precise portraits of Caillebotte and Zandomeneghi.