공주님의 짝사랑 (1967) / One-sided Love of Princess (Gongjunimui Jjaksarang)

The youngest of six royal daughters falls for a scholar she glimpses at her mother's birthday banquet and sneaks out of the palace to find him, trading silk for a disguise she has never needed before. Life outside the walls proves equal parts thrilling and dangerous, but she finds her scholar anyway, over drinks neither of them expected to share.

Why it's free: Free on the Korean Film Archive's own channel; the national archive holds and restores the prints it publishes.