a price on (one's) head
An amount of money being offered as a reward for one's capture, or, in some cases, killing. I'm sorry, but we can't travel with your brother any longer. The sheriff has put a price on his head and it's too dangerous for the rest of us! I'll never be able to live peacefully in this town as long as I have a price on my head.
*a price on one's head
a reward for one's capture. (*Typically: get ~; have ~; put ~; place ~.) We captured a thief who had a price on his head, and the sheriff gave us the reward. The crook was so mean, he turned in his own brother, who had a price on his head.