Valmiki Ramayana 5.2.37

केनोपायेन पशेयं मैथिलीं जनकात्मजाम् ।अदृष्टो राक्षसेन्द्रेण रावणेन दुरात्मना॥

kenopāyena paśeyaṃ maithilīṃ janakātmajām |adṛṣṭo rākṣasendreṇa rāvaṇena durātmanā ||

Our plain-language meaning of this verse is waiting for scholar review.