The poem is narrated by a young woman to an apothecary, who is preparing her a poison with which to kill her rivals at a nearby royal court. She pushes him to complete the potion while she laments how her beloved is not only being unfaithful, but that he is fully aware that she knows of it. While her betrayers think she must be somewhere in grief, she is proud to be instead plotting their murder.
She notes the ingredients he uses, paying particular attention to their texture and color. She hopes the poison will "taste sweetly" so she can poison the two ladies she has in her sights. Though she is a "minion" unlike her competitors, she will have the last laugh by having them killed in a painful way that will also torment her beloved.
When the poison is complete, she promises the apothecary both her fortune (her "jewels" and "gold") but also lets him kiss her. Finally, she is ready to go dancing at the king's and end her torment.
This wicked little poem, first published in Dramatic Romances and Lyrics in 1845, is most notable for the exhilaration of the writing. The rhyme scheme is regular, with an ABAC structure that makes each short stanza playful until the dramatic break of its last line. The voice is wonderfully captured, and we see that this woman is enlivened by more than just revenge; she is invigorated by the power that murder allows her to have. When she first mentions her untrue beloved, she only mentions one woman, but a few stanzas later, she mentions both "Pauline" and "Elise" as targets. She is already being taken away with the potential to kill. While the rhyme scheme is regular, the enjambments stress that she is willing to lose a bit of control, letting this impulse take her.
Further, if winning her husband or lover back were the only goal, she would not take so much glee in the prospect of causing painful death to the ladies and moral torment to him. Her intense focus on the ingredients further confirms the ecstasy she feels at suddenly giving herself over to this wickedness. That this scheme will cost her her "whole fortune" only validates the choice – we get the sense that she will be forever defined by this act. In closing with "next moment I dance at the King's," the poem implies her intent to carry herself as a woman who has accomplished a great deed.
Psychologically, her resentment could be motivated by class expectations. She considers herself a "minion," which probably means a lady-in-waiting or some low-level servant, whereas her competitors are not so lowly. That her beloved is involved with them and that both expect that the speaker is grieving away in an "empty church" is the worst offense. She is considered less worthy than them, which only strengthens her resolve to demonstrate her superiority through the murder.
One could argue that the speaker has never actually been involved with her beloved, since she gives no direct proof of a relationship. Further, as her lover and competitors all know that she is aware of the dalliance, it is possible that they do not even know they are offending her in any way. She could be like the monk of "Soliloquy of the Spanish Cloister," whose hatred and resentment is known only to him. There is also, in the "empty church" line, the slightest indication that perhaps she is a nun, and so her grief would be due to their sexuality out of marriage. Much can be conjectured from Browning's masterful subtly.
Finally, sexuality is presented in this poem as something capable of great grotesqueness. In the same way that the bright, pretty poison will ultimately cause painful death, so does the allure of sexuality have a dark side. Sexuality is certainly behind whatever actions have led this woman to the apothecary, but note her willingness to use it on the apothecary in the final stanza, when she tells him, "You may kiss me, old man, on my mouth if you will!" Certainly, Browning is no prude and we should not read a moral message in this, but rather read it as one of his many uses of objects or values which also contain their opposite. What drives men and women to celebrate life can also cause that life to end.