The Monster Club (1981)

Renowned author R. Chetwynd Hayes (John Carradine) is approached by a mysterious, half-starved stranger named Aramis (Vincent Price). After Hayes makes an involuntary blood donation near a dark alleyway, Aramis reveals that he is a both a fan of the author's work and a vampire. To compensate him for his blood loss, Aramis invites Hayes to an exclusive club where he shares tales of his fellow monsters.