In the novel "Over Sea, Under Stone" by Susan Cooper, Great-Uncle Merry exhibits an unusual expression that captivates the attention of Jane. His eyes appear unfocused, suggesting a sense of distraction or contemplation. Despite this, there is a noticeable twitch at the corners of his mouth, indicating a complex emotion, perhaps hinting at happiness even in the absence of a traditional smile.

The juxtaposition of his typically sad demeanor against this moment of apparent joy highlights a significant transformation in his character. Jane notices this difference keenly, realizing that the change in his expression brings a newfound brightness to his usually somber presence, making it all the more impactful.