She asks Stanley’s friend Mitch to cover the bare light bulb in the room with it, saying “I can't stand a naked light bulb, any more than I can a rude remark or a vulgar action”. She is obviously flirting with Mitch and perhaps because of it she wants the lantern to be placed there in order to hide the marks of age, hard life, and alcoholism on her face. Symbolically, the placing of the colored lantern represents Blanche’s attempt to hide her past from a potential new suitor, but also from herself, as she is shown throughout the play to be unable to face up to the realities of her life, past and present.

Blanche also wants to present herself as sensitive and gentle, saying people like her need to show “the colors of butterfly wings, and put a—paper lantern over the light,” so the lantern also represents her attempt to construct and believe in an idealized image of herself.

Near the end of the play, Mitch, who has found out the hard truths about Blanche, roughly tears down the paper lantern in order to “take a look at you good and plain.” Blanche, horrified, replies: “I don't want realism. I want magic!”, implying that the lantern was for her a device to fend off the harsh reality of her life and an attempt to produce an illusion, but again primarily for herself, for this is what she needs to survive in the real world. This is why in the stage direction Tennessee Williams writes that the tearing down of the lantern hurts Blanche “as if the lantern was herself.” Blanche cannot remain sane without her illusion: the colored light of the paper lantern.