In the Shadow of the Guillotine by Rafael Sabatini

ANGÈLE'S first feeling of thankful amazement at the escape which Seyrac had through his very treachery contrived for Vidal, passed quickly into one of utter despondency when she came to consider the position at closer quarters.

She saw clearly that after all there was no escape but merely a respite. Seyrac had plunged headlong to his own doom. His own baseness had enmeshed him with a justice truly poetic. But it was not to he supposed that the mistake which had occurred would long continue undiscovered.