At Qingyun High School, a provincial-level key school, art student Lin Zhi and top science student Shen Shuyan are brought together by a mysterious sketchbook. Lin Zhi's charcoal sketches and Shen Shuyan's mathematical annotations intertwine across its pages, while the romance of Gothic architecture clashes with the rigor of structural mechanics in a play of light and shadow.
From their first standoff at the basketball court to an exhibition of light and shadow at the art museum, from a warming incident in the library to their collaborative installation for the arts festival, the two boys, so different in temperament, seek balance between reason and emotion. When intensive art exam prep triggers a crisis of trust, a heart-to-heart on a rooftop during a storm reveals the truth. They discover that the Mobius strip in the sketchbook has long bound their fates together.
This is an encounter about youth, dreams, and growing up. When the cold formulas of an architectural dynasty meet the warm strokes of an artistic girl, and rational calculations precise to the millimeter meet a flutter of the heart that no data can measure, they will eventually find the light meant for them in the refractive index of dusk.
