Mass Effect Legendary Edition

This is for recruiting Thane. He will appear in the second half of crew member additions after you progress in the story. The mission to unlock this achievement is titled, Dossier: The Assassin.

If you are struggling with the mission or would like some more insight the following link will help with everything mission related. (https://masseffect.fandom.com/wiki/Dossier:_The_Assassin#Pre...)