Esther 2:21-23

21In those days while Mordecai was sitting at the king’s gate, Bigthan and Teresh, two of the king’s eunuchs who guarded the doorway, became angry and conspired to assassinate King Ahasuerus.

22But Mordecai found out about the plot and told it to Queen Esther. Esther informed the king in Mordecai’s name.

23When the matter was investigated and found to be so, they were both hanged on a gallows. It was then written in the book of the chronicles in the king’s presence.