The Book of Ruth is short-story length: too long to read together in a session which also explores other sources, but reasonable for reading at home, or in a dedicated class. The JPS translation is a good starting place, but feel free to use any version.

Here is an edited version of Wikipedia’s summary:

During the time of the Judges when there was a famine, an Israelite family from Bethlehem – Elimelech, his wife Naomi, and their sons Mahlon and Chilion – emigrated to the nearby country of Moab. Elimelech died, and the sons married two Moabite women: Mahlon married Ruth and Chilion married Orpah.

After about ten years, the two sons of Naomi also died in Moab (Ruth 1:4). Naomi decided to return to Bethlehem. She told her daughters-in-law to return to their own mothers, and remarry. Orpah reluctantly left; however, Ruth said, “Do not urge me to leave you, to turn back and not follow you. For wherever you go, I will go; wherever you lodge, I will lodge; your people shall be my people, and your God my God. Where you die, I will die, and there I will be buried. Thus and more may God do to me if anything but death parts me from you” (1:16–17).

The two women returned to Bethlehem at the beginning of the barley harvest, and in order to support her mother-in-law and herself, Ruth went to the fields to glean. As it happened, the field she went to belonged to a man named Boaz, who was kind to her because he had heard of her loyalty to her mother-in-law. Ruth told Naomi of Boaz’s kindness, and she gleaned in his field through the remainder of the barley and wheat harvest.

Boaz was a close relative of Naomi’s husband’s family. He was therefore obliged by the Levirate law to marry Mahlon’s widow, Ruth, in order to carry on his family’s inheritance. Naomi sent Ruth to the threshing floor at night and told her to go where he slept, and “uncover his feet [which some commentators consider a Biblical euphemism for private parts], and lie down; and he will tell you what are to do” (3:4).

That night, Boaz “ate and drank and his heart was in a cheerful mood” (3:7). After he lay down on the threshing floor, Ruth did as Naomi had instructed her. Boaz, startled, turned to see that a woman lay at his feet. When asked who she was, she replied: “I am your handmaid Ruth. Spread your robe over your handmaid, for you are a redeeming kinsman” (3:9). Boaz blessed her and agreed to do all that was required, and he noted that, “all the elders of my town know what a fine woman you are” (3:11). He then acknowledged that he was a close relative, but that there was one who was closer. Boaz told Ruth to stay with him for the night, and promised that in the morning he would offer the closer relative the opportunity to redeem her, and that if the relative refused, Boaz himself would marry Ruth. Ruth remained “at his feet” until she returned into the city in the morning, before anyone else woke up.

Early that morning, Boaz discussed the issue with the other male relative, Ploni Almoni (“so-and-so”), before the town elders. The other male relative was unwilling to jeopardize the inheritance of his own estate by marrying Ruth, and so relinquished his right of redemption, thus allowing Boaz to marry Ruth. They finalized the agreement by the nearer kinsman, Ploni Almoni, taking off his shoe and handing it over to Boaz (4:7–18). Boaz and Ruth were married in the presence of the town elders and “all the people at the gate,” and had a son named Oved: who is “the father of Jesse, the father of David” (4:13–17). Later, Boaz died, and Ruth and Naomi raised Oved together.