Planejammer: The Seven Stars
The Illithid researcher who hired the Seven Stars to take him to the Outpost of the Elders. Once inside he mindwalked out at the first sign of trouble, taking with him a piece of the trilateral helm. This gave him the physical evidence of the Elders he wanted, but left the party in a suddenly inert ship facing an angry sephardin.
This was the mission that made the Seven Stars rich.
It was only years later that the Seven Stars realized that by taking that mission they had provided the Illithids with the final component needed for their Overmind project