As the title implies, a major motif of the play is the sea. The sea is made ever present in the play by the dialogue; the characters constantly reference the sea, how dangerous the sea is, having to cross the sea to sell wares, and what they have lost to the sea. The sea is a symbol of the power of the natural world. It is both a provider and destroyer for the inhabitants of the Aran Islands. The land of the islands is rocky, so the islanders cannot grow enough food for self-sufficiency. Instead, they must travel the rough seas between the islands and mainland Ireland to sell their wares at markets and fairs in Connemara. The weather, however, is often stormy, creating dangerous sailing conditions. As a result, the islanders often lose fathers, husbands, and sons to the sea, as Maurya has many times over.

The sea, however, does not function only as a symbol of life and death; the sea is the driving force of the play. The plot moves forward through the behavior of the sea as it returns the belongings of one son to the island and takes the life of Maurya’s final son.