The novel traces the paths of a group of Dubliners through an ordinary summer day: 16 June 1904.

Ulysses is the Latinised name of Odysseus, the hero of Homer's epic poem the Odyssey, and the novel establishes a series of parallels between the characters and experiences of Leopold Bloom and Odysseus, Molly Bloom and Penelope, and Stephen Dedalus and Telemachus.

Although Bloom is of partial Jewish descent, he converts to Catholicism to marry Marion (Molly) Tweedy on 8 October 1888.

Molly has an affair with her manager, Hugh 'Blazes' Boylan.

Buck Mulligan later chastises him, saying, "You wouldn't kneel down to pray for your mother on her deathbed when she asked you. Why? Because you have the cursed jesuit strain in you, only it's injected the wrong way.

The sacred pint alone can unbind the tongue of Dedalus.

The last episode in the book both begins and ends with "yes," a word that Joyce described as "the female word" and that he said indicated "acquiescence, self-abandon, relaxation, the end of all resistance."

MOLLY: I was a Flower of the mountain yes when I put the rose in my hair like the Andalusian girls used or shall I wear a red yes and how he kissed me under the Moorish Wall and I thought well as well him as another and then I asked him with my eyes to ask again yes and then he asked me would I yes to say yes my mountain flower and first I put my arms around him yes and drew him down to me so he could feel my breasts all perfume yes and his heart was going like mad and yes I said yes I will Yes.

Mr. Bloom raised a cake to his nostrils. Sweet lemony wax.
--I'll take this one, he said.

Gerty MacDowell who was seated near her companions, lost in thought, gazing far away into the distance was in very truth as fair a specimen of winsome Irish girlhood as one could wish to see.

Bloom reads a letter from his daughter, Milly Bloom, who tells him about her progress in the photography business in Mullingar.