Hollywood changes everything. A series of successful films and the commonly-held view of things changes. ‘Vampires turning to ash in sunlight’ is a good example. In Dracula, the Count can walk in the daylight but he hasn’t the power to turn into animals or smoke. This literary rigor mortis also happened to the werewolf. The Werewolf of London (1935) and then The Wolf Man (1941) pretty much cemented the werewolf legend into a single track of silver bullets and wolfsbane.
But it wasn’t always so. The werewolf legend had its classics, each different, each exploring a different part of a wide range of ideas. For the agrarian people of the past, the werewolf’s terror wasn’t because they ate human flesh but preyed upon livestock. The werewolf in Petronius’s The Satyricon attacks Melissa’s sheep, not the woman herself. The Medieval werewolf is often a cursed individual paying penance for some crime, a pathetic figure.
It is only with the Victorians, people now largely removed from the country, that the werewolf becomes something else. A monster prowling amongst us, usually as a foreigner, fed by all the xenophobic fears of a crumbling British empire. Bram Stoker’s werewolves in “Dracula’s Guest” and on the ship in Dracula are closely linked to vampires, both being Count Dracula in another form. Despite this, the 1897 novel did inspire many new tales of werewolfry.
H. P. Lovecraft in his essay “The Supernatural Horror in Literature” clearly saw The Door of the Unreal as a descendant of Dracula. Biss’s novel does borrow from Stoker in that it features a group of men stalwartly facing a supernatural force. In Dracula, Lord Godalming, Van Helsing, Harker and several others kill the resurrected Lucy Westerna. Lincoln Osgood acts in the Van Helsing role of ghostbreaker and leader while Burgess is Lord Godalming and Bullingdon is Jonathan Harker. Poor Wuffles is sacrificed much as is Lucy Westerna while the soon-to-be-werewolf Dorothy is the pursued Mina Harker.
But to write The Door of the Unreal off as a Stoker clone is to miss several innovations that took place with this book. Biss spends the first third of the book building a façade of factuality in an attempt to calm the reader’s incredulity. Stoker did this to a lesser degree by using journal entries, but Biss goes a step further with sworn statements and tedious addendums. (Lovecraft would use similar techniques of simulated factuality in his Cthulhu Mythos fiction.) The second section of the novel is largely talking heads as Osgood maneuvers his allies. Unlike Dracula, where we know of the Count’s vampire nature by Chapter Four, Biss doesn’t even breathe the word “werewolf” until half way through the book. The last and best third contains the final showdown and a few genuine thrills — a long time to wait by modern standards. Even by the standards of the 1930s Pulps. Seabury Quinn could tell the same story is about 30 pages. (In fact I think he did, eight times.)
The structure of The Door of the Unreal is unusual. The closest novel to it structurally is Frederick Forsyth’s The Dogs of War, in which ninety percent of the novel is spent watching mercenaries prepare for a coup. Only the last segment contains any real action. The interest for the reader is equivalent to meticulously learning how to fire a cannon then setting one off. The build up is essential to making the entire production mean anything. I suspect The Door of the Unreal works in a similar way. To simply describe a group of men surrounding a house and killing two werewolves (sans silver bullets) would be largely ineffective. The build up of the Bosolver Disappearance and then the tragedy of Bullingdon and St. Clair are necessary to hook our interest, while the middle section allows us to know the characters and to care about their fate and then and only then do we see the destruction of Professor Wollf and Anna Brunnolf. The entire process is cathartic in the old Greek theatrical way. 
Something this novel does not do is portray anything from the werewolf’s perspective. That innovation would come six years later when H. Warner Munn would pen “The Werewolf of Ponkert” for the July 1925 Weird Tales (from a suggestion by H. P. Lovecraft) and even more brilliantly in 1933 in The Werewolf of Paris by Guy Endore. Biss does nothing to engender us to the werewolves. Quite the opposite. Lycurgus Wolff is a vile creature and we are only too glad to see him die. Unlike Larry Talbot of The Wolf Man, Biss’s werewolves are not victims of curses to be pitied but an insidious poison that plots and schemes, threatening all of England and humanity as we know it.
The Door of the Unreal is a werewolf classic. Written in 1919, it is one of the last of the free lycanthropic tales before the coming of Hollywood, before the Pulps and Television. Biss had free reign to select from the mass of werewolf legends as exemplified by the acknowledged masterwork, Eliott O’Donnell’s Werewolves. Biss wrote only this one last Edwardian gem, despite an over-abundance of modern paraphernalia such the ‘phone, repeater rifles and speedy motor cars. For all its modernity, The Door of the Unreal is a final farewell to the Victorian werewolf. Long may he run.