be after/out for somebody's blood
be after (one's) blood
To seek revenge on another person. He hit my car, so I'm after his blood now.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
be after/out for somebody’s ˈblood(informal, often humorous) want to hurt or harm somebody, especially as revenge: They have been after my blood ever since I accidentally damaged their car.
Farlex Partner Idioms Dictionary © Farlex 2017