Commander Robert Ellis is an unseen character in the TV series. He is a Commander in the Republic of Gilead, as well as (presumably) being a member of the Sons of Jacob. He is the head of the household in which Alma is enslaved as a Handmaid.
In the Present Edit
Season One Edit
At a particicution, Alma stands next to June and reveals that she has been assigned to Commander Ellis. She confides that he "can barely get it up" and implies that he is lower-ranked compared to Commander Waterford.