。
She gets really scared in dark places.
Literal
She [topic-は] dark place [object-を] very is-fearful-of.
怖がる is the がる-suffixed verb form of 怖い ('scary'), describing externally observable fear behavior — used for third parties since Japanese restricts directly attributing inner feelings to others. The を on 暗いところ marks the source of fear as the verb's object, parallel to 恐れる. ところ ('place') here generalizes 'wherever it's dark.' とても ('very') intensifies. The whole sentence frames a recurring trait, not a specific moment.