Elan, a young vampire hiding among humans with the help of synthetic blood, applies for a job as the assistant to the cold and ruthless CEO Cyrus. But he finds himself irresistibly drawn to Cyrus's blood. Cyrus, in turn, discovers that Elan's presence eases the excruciating headaches caused by his pureblood lineage, so he forces Elan to stay by his side. Both mistakenly believe the other is human and go to great lengths to conceal their true identities. Meanwhile, vampire hunter Mae acts like a meddling matchmaker while secretly investigating them. At the same time, Vincent, the leader of the Vampire Alliance, plots to use Elan to destroy Cyrus and establish vampire rule over humanity. What begins as an unusual office relationship soon spirals into a full-blown vampire rebellion.