Jacinthe is surprised one night (Visite nocturne, t5, Michel, 1801) - Wedding after Challiou

Jacinthe has taken refuge with Mrs. Sinclair, who is none other than the sister-in-law of her father, whom she doesn't yet know, Lord Endermay. One night when she is staying in a remote part of Mrs. Sinclair's castle, a person whose figure she can only make out enters the study and observes her in the dark before running off. It turns out to be a maid from the Endermay family, who knows all about the family crimes that separated Jacinta from her father at birth. Surprised to recognize a face she thought had disappeared after wandering around such a gothic castle, she cries out and flees.

That's what this image seems to represent, unless it illustrates a scene present in Volume 4: Jacinta, then locked in the castle, had received help from a shepherd in the middle of the night who offered her escape by running away.