On the night before the English prisoners were to start on their journey southwards to be exchanged with Scottish nobles—­an exchange after which, by England’s will, the war was to continue—­Lady Mar, whose husband was now governor of Stirling Castle, gave a banquet in honour of the departing knights.  The entertainment was conducted with that chivalric courtesy which a noble conqueror always pays to the vanquished.

But the spirit of Wallace was sad amid the gaiety; seeking quiet, he wandered along a darkened passage that led to the chapel, unobserved save by his watchful enemy De Valence—­whose hatred had been intensified by the knowledge that Helen, whose hand he had again demanded in vain, loved the regent.  He had guessed her secret, and she had guessed his—­the design he had of murdering the foe who had twice spared his life.

As Wallace entered the chapel and advanced towards the altar, he saw a woman kneeling in prayer.  “Defend him, Heavenly Father!” she cried.  “Guard his unshielded breast from treachery!” It was Helen’s voice.

Wallace stepped from the shadow; Helen was transfixed and silent.  “Continue to offer up these prayers for me,” he said gently, “and I shall yet think, holy maid, that I have a Marion to pray for me on earth, as well as in heaven.”

“They are for your life,” she said in agitation, “for it is menaced.”

“I will inquire by whom,” answered he, “when I have first paid my duty at this altar.  Pray with me, Lady Helen, for the liberty of Scotland.”

As they were praying together, Helen rose with a shriek and flung her arms around Wallace.  He felt an assassin’s steel in his back, and she fell senseless on his breast.  Her arm was bleeding; she had partly warded off the blow aimed at him, and had saved his life.  He took her up in his arms, and bore her from the chapel to the hall.

“Who has done this?” cried Mar, in anguish.

“I know not,” replied Wallace, “but I believe some villain who aimed at my life.”  With a gasp he sank back unconscious on the bench.

Helen was the first to recover, and while they were staunching the blood that flowed from Wallace’s wound, Lady Mar turned to her step-daughter.

“Will you satisfy this anxious company,” said she sneeringly, “how it happened that you should be alone with the regent?  May I ask our noble friends to withdraw, and leave this delicate investigation to my own family?”

Wallace, recovering his senses, rose hastily.

“Do not leave this place, my lords, till I explain how I came to disturb the devotions of Lady Helen;” Straightforwardly and with dignity, he told the story of what had happened, and the jealous Lady Mar was silenced.

“But who was the assassin?” they asked.

“I shall name him to Sir William Wallace alone,” said Helen.

But the dagger, found in the chapel, revealed the truth.  The chiefs clamoured for De Valence’s death, Wallace again granted him life.  Next morning, as the cavalcade of southern knights was starting, Wallace rode up and handed the dagger to De Valence.