The padre feels the call to preach to the wilder tribes and ascends the tortuous trails to the mountain village home of Conchita, where he teaches the Indians kindly ways and good deeds. Conchita, daughter of Pedro, is impressed by padre's earnest teachings and is prevailed on to accompany him down to the mission to be instructed. The days pass and happy hours with Conchita awaken forbidden love in the padre's heart, which he conquers only by the timely arrival of Ricardo, a Spanish grandee, who woos and wins Conchita and marries her. But another, El Sombriado, the black one from the mountains, has a life-long love for Conchita, companion of his boyhood days, and having lost her through marriage, he comes down to the mission and slays Ricardo even as the ceremony is concluded. Conchita takes her oath of vengeance and follows El Sombriado to the mountains. She in turn is followed by the padre. At the wayside shrine she renews her oath, and the padre, close on her heels, is in the meantime captured by El Sombriado and a few renegade friends. Conchita discovers the padre a prisoner and releases him, to be followed by El Sombriado and his men. A meeting takes place beneath the wayside shrine and El Sombriado, now maddened by jealousy, attacks Conchita with his knife. Conchita, fresh from the renewal of her oath, meets him, knife in hand, and in the struggle that follows El Sombriado falls back against the cross of the shrine. Aged by time and weather, the arm of the cross falls and, striking the "black one" on the head, ends his life. The padre offers a prayer over the dead Indian, while the others flee in terror, thinking the punishment of El Sombriado divine. Conchita is returned to her mountain home by the padre, who then seeks solace in the rosary and cell, while Conchita goes back to her father's home, her oath fulfilled.
—Moving Picture World synopsis