[2] He is Count Dracula's deranged, fanatically devoted servant and familiar, helping him in his plan to turn Mina Harker into a vampire in return for a continuous supply of insects to consume and the promise of immortality.

In the various film adaptations of the novel, he has been portrayed by actors such as Alexander Granach, Dwight Frye, Roland Topor, Tom Waits, Peter MacNicol and Simon McBurney.

Sanguine temperament, great physical strength, morbidly excitable, periods of gloom, ending in some fixed idea which I cannot make out.

However, when confronted by Mina Harker, Dracula's latest victim, Renfield suffers an attack of conscience and begs her to flee from his master's grasp.

Consumed by his desire to keep Mina safe, he begs Seward and the others to allow him to leave lest he feel guilty for her fate.

The vampire hunters enter the room shortly afterward, and through an emergency surgery Van Helsing manages to prolong Renfield's life.

First, Dr. Seward told us that when he and Dr. Van Helsing had gone down to the room below they had found Renfield lying on the floor, all in a heap.

The character Renfield has influenced the study of real-life behavior in psychiatric patients with an obsession with drinking blood.