By Kristen Tregar

Both on the stage and on the screen, Frederick Knott’s masterpiece Dial M for Murder is widely acknowledged as one of the finest thrillers ever written. The play premiered at the Westminster Theatre in London in June 1952 and subsequently went on to an enormously successful run in New York City. The play was so popular that Warner Brothers purchased the film rights, allowing Alfred Hitchcock, the “Master of Suspense,” to bring Knott’s tale of murder and betrayal to the screen in 1954.

But what made Dial M for Murder so well received? Knott only wrote a handful of plays, so his reputation alone was insufficient to drive its reception. Instead, Knott’s crafting of Dial M for Murder deftly incorporated the two most important elements of any thriller: suspense, and that skin-crawling feeling spectators experience when something that is usually safe and familiar becomes the exact opposite, sometimes referred to as “the uncanny.”

Thrillers themselves may feel relatively modern, but in fact, the genre is quite ancient. Some of the great epic poems of antiquity, like Homer’s Odyssey, shared characteristics and used plot devices similar to those found in present-day thrillers. Perhaps the most notable among these is suspense, which has been a part of great storytelling long enough that even Aristotle described its value in Poetics.

According to Alfred Hitchcock, suspense requires an audience who knows as much information as possible. The central question of a thriller is “how”: how will the killer be caught? How will an innocent person accused of a crime be vindicated? This marks the thriller as distinct from mysteries, which focus on the identity of the crime’s perpetrator. In a thriller, the audience typically knows early on who the criminal is and they can see and anticipate the action unfolding.

Audience knowledge marks a distinction between an event that is suspenseful and one that is surprising. In Hitchcock’s interviews with the filmmaker François Truffaut, he explains the difference between these two often-confused emotional states with a simple story involving a bomb. If an audience observes a conversation between two people and suddenly a bomb the audience was unaware of explodes, that is surprising. But, if the audience sees the conversation, sees the bomb, and can anticipate when the bomb is likely to explode, that knowledge inspires suspense. The audience is led to a heightened emotional state of anticipation, of hope that somehow the explosion will be stopped or the characters will make it to safety in time, and of desire to find a way to warn the characters of the impending danger in which they find themselves.

In Dial M for Murder, the audience is positioned as an uninvited voyeur in the dialogue between two characters who plot a murder. As a result, the entire plan is made visible from the outset, the audience is aware of the characters’ treachery in advance, and they have no choice but to sit in anticipation of the events that will unfold. And yet, there are still surprises in store! Things don’t go quite as expected, resulting in a shift in plans, and the question of how the truth will come to light remains open until the very last moments of the play.

But suspense (and the occasional surprise) alone are not enough to create a truly great thriller. What many of the most memorable thrillers have in common is that they make ordinary lives and places seem strange and suddenly dangerous: they include elements of what Sigmund Freud called “the uncanny.” The term refers to a feeling that most people have experienced but that is challenging to fully describe or name. It’s the eerie sensation one has when presented with an object, space, or situation that is familiar but unfamiliar at the same time. The most classic example is the feeling you get when looking at an extremely realistic wax figure (or in more modern times, an incredibly lifelike robot). It might seem almost alive at first, but viewed for more than a moment, it becomes clear that something is not quite right.

In Dial M for Murder, the uncanny presents itself slightly differently. Rather than an object or form creating a sense of disconnection, it is the space itself—the home—that creates a disturbance for the viewer. The setting of the play is the Wendice apartment. Typically we think of homes as places of safety and respite from the pressures of the world, but as the play unfolds, it becomes clear their flat is anything but a safe home. And while the murder plot at the center of the story is ultimately unearthed within the space of that same apartment, the security of the home is never fully restored.

Hitchcock’s film of Dial M for Murder developed the viewers’ feeling of the uncanny even further by shooting it in 3D technology to bring the spectator right into the action. In the early 1950s, audiences were still being introduced to 3D techniques, and the experience was quite a departure from sitting comfortably in a theatre seat and watching the action unfold simply on the screen. Instead, 3D provoked a sense of mistrust in the viewer’s perception: they knew they were in the cinema and yet found themselves simultaneously within the space of the film. That sensation added to the overall feeling of insecurity developed by the film’s narrative itself. It remains the only film Hitchcock ever filmed in 3D.

While Knott authored only a few plays, he quickly demonstrated his mastery of the use of both suspense and the uncanny to provide a thriller that continues to inspire audiences over 50 years later. By allowing the audience access to everything they need to know to see the danger arising, he manages the spectator’s anticipation and their hope that all will work out in the end.

Kristen Tregar received her Ph.D. from the joint program in Theatre at UC San Diego and UC Irvine. Previously she earned an M.S. in Forensic Science from John Jay College of Criminal Justice in New York City and spent a year as an intern with the Westchester County Department of Public Safety, assisting the Identification Unit with crime scene processing, fingerprint analysis, and ballistics.