a wolf in sheep's clothing

US /ə wʊlf ɪn ʃiːps ˈkloʊðɪŋ/
UK /ə wʊlf ɪn ʃiːps ˈkloʊðɪŋ/
"a wolf in sheep's clothing" picture
1.

um lobo em pele de cordeiro

a person who appears friendly or harmless but is actually dangerous or malicious

:
Be careful of him; he's a wolf in sheep's clothing.
Cuidado com ele; ele é um lobo em pele de cordeiro.
The new manager seemed nice at first, but he turned out to be a wolf in sheep's clothing.
O novo gerente parecia legal no início, mas ele se revelou um lobo em pele de cordeiro.