We report on a single star , B030D , observed as part of a large survey of objects in M31 , which has the unusual radial velocity of -780 km s ^ { -1 } . Based on details of its spectrum , we find that the star is an F supergiant , with a circumstellar shell . The evolutionary status of the star could be one of a post-mainsequence close binary , a symbiotic nova , or less likely , a post-AGB star , which additional observations could help sort out . Membership of the star in the Andromeda Giant Stream can explain its highly negative velocity .