He Came... And Went

He Came... And Went is a side quest in the Fallout: New Vegas add-on Old World Blues.

Quick walkthrough

 * Talk to Dr. Dala about the "other visitor" to Big Empty.
 * Find out the questions the other courier asked Dr. Klein.

Detailed walkthrough
After visiting the think tank and talking to Dr. Klein, he will tell you to talk to the other doctors. After talking to Dr. Dala you will learn that another courier traveled to the Big Empty and that he was looking for another courier but hadn't found the right one yet. She can't recall the questions he asked, but hints that Dr. Klein might know. Talk to him to learn about the other courier.