Note: I've always enjoyed the Scarlet Pimpernel, and Antony Andrews' portrayal is masterful. This takes place in the film starring Antony Andrews and Jane Seymour, just after the wedding reception for the Blakeneys, when Sir Percy has learned from Baron de Batz what happened to the St Cyrs and why.
Percy may have been firm in his resolve to his men, but his heart was another matter. Silently he watched his bride prepare herself to grace his bed, from his position upon the threshold of the room, doubt after doubt running through his mind. Aside from her vow about the St Cyrs the night they met, her principles, morals, and beliefs matched his. She held no love for the bloodlust which her country's revolution had acquired.
If she had been serious in her words she could have acted on them before now. No, the timing of their execution was too auspicious not to be questioned. Likewise the creditability of his source. That the Baron de Batz was an agent for Austria as well as France was one of the worst kept secrets of the revolution. Percy himself discovered that before he became the Scarlet Pimpernel. As for Chauvelin, he was in charge of France's intelligencers and he had more than one grievance to desire revenge on Margeurite and himself. He could have easily forged Margeurite's signature on the warrant.
It was a good alternative and one Percy would dearly love to confirm. Tony had not believed the Baron either, and he would do well to listen to other members of his league. But how to ask her without accusing her?
Fortunately for him, Margeurite happened to look up and notice his presence. Something of his preoccupation must have shown in his countenance for when she spoke, it was as if she knew his thoughts.
"What was it that the Baron de Batz said to cause you such concern?" she inquired.
"I had not realised that you noticed," Percy remarked, remaining in his seemingly careless pose by the door.
"How could I not?" Margeurite countered. "I was coming to claim your hand for our dance. But you have not answered my question."
Percy took a breath, then began. "He told me that the St Cyrs were executed today."
Margeurite stilled, her hand upon her mouth in shock. "Mon Dieu," she uttered softly. "All of them?"
Percy said nothing but his silence was a more than eloquent response. Instead he observed her reaction. Marguerite's grief over the loss of life was readily apparent and justified, also entirely genuine. But so too was the guilt, which troubled him deeply. Not until now had he believed what the Baron told him. His caution to his men was that of a chief, decisive and instant, while his heart screamed in protest. That organ was screaming still, in grief of loss. Wretched, he had to rouse himself from the inner turmoil as soon as he realised she was still talking, though what she spoke first appeared to damn her further.
"My fault," Marguerite uttered. "I should have burnt it, not kept it for him to find." she looked up at this, and the confused turmoil must have shown upon his face, for she began to explain.
"The Baron de Batz was at the soiree Armand and I held, the one I invited you to. He left before you came; Chauvelin offended him. The Baron had a letter which he threw into the fire. A fragment flew out of the flames' reach and I picked it up. It didn't say much, but what it say was damning. 'You can inform your people that the dauphin is to be held in the Temple. St Cyr.' I didn't intend to do anything with it. The knowledge that I had a means of revenge was enough. I could never live with myself if my actions caused his death, and that of his family. But now I wished I had burned the letter, for Chauvelin was rifling through my correspondence one day and found it. He told me he would not use it, but he did as soon as he heard of our engagement. I am the cause of their deaths, no matter how I begged otherwise."
Percy listened to all this in a shock of grief so profound that tears broke his habitually inane mask before he was even aware of them. His thoughts punished him now, reminding him of the doubts of Lord Dewhurst, disciplined him for believing a double agent such as Baron de Batz over the woman he loved and the man who swore to lay down his life for him and France when they formed the league.
The secret of which she could be trusted with now and with that revelation realised, he was crossing the space between them to kneel before her feet, his hands reaching to clasp hers. "If you are to blame, my darling, for being betrayed by these treacherous times, so am I for insisting all of the league attend our wedding feast. If they had not, a rescue might have prevented the guilt which you should not feel." He squeezed her hands as her eyes met his in wonder. "If we let this torment us, then Chauvelin wins, for he must have intended as much."
"Insisted," she echoed, "the league... Percy are you..." she lost her voice, too amazed to finish the query.
He answered it for her, by placing his signet ring in her hand, the sapphires reversed to reveal the humble wayside flower engraved into the gold below. Her eyes took in the confirmation in one glance, the risks he took never escaping her. Then her eyes returned to his, wondrous in the addition of this facet to his character, the elusiveness she could not fathom past before, all but faded away.