Engrossed in experimental work, Dr. Walker neglects his wife and child. Elena comes to the conclusion that he no longer cares for her. Jack Tremond, an artist once a suitor for Elena's hand, learns the state of affairs. He urges the woman to elope with him, but Elena turns a deaf ear to his pleas. Her husband's neglect becomes unbearable. A sudden impulse rashly causes Elena to decide to leave him. After putting her child to sleep one evening, Elena places a note, giving the reasons for her step, on the nursery table. Meeting her husband while leaving the house, Elena informs him she intends to visit a friend. The woman hastens to Jack's studio, but finds he has just left. Deciding to wait, she makes herself comfortable in an easy chair. A painting, depicting a primitive man attracts Elena's attention. The woman falls asleep while gazing at the picture. Elena dreams she sees the cave man win a mate in combat with a rival savage. Later, the primitive woman, believing herself neglected, becomes angry with her mate's interest in the fashioning of new weapons, and prepares to run away with his rival. Realization of his love comes when she sees him in fierce combat with a ferocious lion that menaces the safety of their child and herself. Elena awakes with a start. The moral of her dream strikes home. The woman hastens from the studio just before Jack's return. In the meantime, a lamp accidentally upsets, sets fire to the nursery. His baby's screams bring Dr. Walker to the scene. After rescuing the child, Robert subdues the flames with his naked hands. Elena's letter is consumed in the fire. The wife returns home and learns what has transpired. Realizing the depths of his father-love, Elena kisses her husband's blistered hands.
—Moving Picture World synopsis