babe(s) in the woods

A person who is gullible, naïve, or lacks experience in a specific situation. Although Jane had always excelled in school, she felt like a babe in the woods when she began attending college. Julia's a babe in the woods, so I bet we can trick her into stealing the test answers for us. A babe in the woods like you won't make it in such a cutthroat industry.

Extremely naive or innocent individual(s). The term comes from a popular ballad, “The Children in the Wood” (1595), about two orphaned children. Their wicked uncle wants their inheritance and hires two men to murder them. One of the men repents and kills the other, but he abandons the children in a deep forest, where they die. The tale was kept alive by numerous writers, notably through Thomas Percy’s collection, Reliques of Ancient English Poetry (1765).