All war is hell, as William Sherman once said, but World War I in many ways was the most hellish war of all time, especially for the European countries. For four years, British, French, and German armies dug in to elaborate trench and defense networks and slugged it out, often incurring horrendous losses in head-on attacks that, even when successful, gained little ground and no real advantage. All the while, those at home received word of dead, maimed, or missing loved ones.

It’s no surprise that many in Great Britain and other European countries became pacifists as a result of their wartime experiences. One of the most English prominent pacifists was Vera Brittain, a woman who experienced the shock of World War II firsthand as a battlefield nurse. Testament of Youth, her memoir based on those experiences, became an influential best seller and is now considered a classic. Now, a century after the main events in the book took place, Testament of Youth becomes a motion picture worthy of its literary forebear.

For those unfamiliar with its subject matter, the events shown in Testament of Youth may come as quite a shock. As the film opens in the months immediately prior to World War I, Vera (Alicia Vikander) was a typical daughter of an upper middle class family, well-to-do enough not to work and expected to engage in leisurely pursuits until finding a suitable husband. However, she is far more ambitious, wanting to attend Oxford. Her biggest supporter in that regard is her beloved brother Edward (Taron Edgerton), an Oxford man himself. Edward helps convince Vera’s parents (Dominic West and Emily Watson) to let her go off to Oxford, where she studies literature in the hopes of becoming a writer.

In addition to acquiring a love for the classics, Vera also acquires a love for one of Edward’s friends, Roland Leighton (Kit Harrington). However, their courtship, as were many others in England at that time, was interrupted by World War I. Edward wants to enlist, and, this time around, Vera, convinced the war will be over soon and that military service will be good for Edward’s future, helps persuade her parents to let him do so. Roland also enlists, as does another family friend, the closeted Victor Richardson (Colin Morgan).

With the war expanding and casualties mounting, Vera is no longer content to sit on the sidelines at Oxford, so she volunteers to become a nurse, first in England, tending to wounded soldiers who have returned from the front, and then to France. The scenes in France are by far the most intense in the film and, honestly, some of the most harrowing I’ve seen. The footage isn’t that graphic, at least by horror porn standards, but it’s authentic (director James Kent used Afghan war amputees as extras in these scenes). And, it’s not the horror of the individual patients that’s stunning, it’s the enormity of the carnage. In the most visually impressive scene in the movie, Vera is shown tending to a wounded soldier outdoors (there aren’t enough beds), and the camera pans back to show the rows and rows of dead and dying soldiers lined up around her patient.

Testament of Youth has almost no actual battlefield footage, choosing instead to show the reaction of those in England to the increasingly devastating casualty reports. What was at first a grand adventure quickly becomes month after month of awaiting the worst news. The fact that the audience, like Vera, has been sheltered from the real face of war until she arrives in France makes the footage that much more compelling.

I don’t want to give away any of the plot details because to say anything would spoil the impact the war news has on Vera and others. However, since Testament of Youth is based on Vera’s memoir, many people will be well aware of just what impact the war has on her. However, it’s not the bad news itself, but how Vera’s reaction to it changes over time, that allows viewers a glimpse into her character.

The seminal event in Vera’s wartime experience is her first combat duty. Sent to tend to a ward of maimed and dying soldiers, she soon realizes she is treating German prisoners who are unlikely to live much longer. However, although their cries and prayers are in a foreign tongue, their suffering is universal, and this experience led the real-life Vera to make the ending of future conflicts her life’s work.

The role of Vera is the best yet for Alicia Vikander, who garnered (a bit undeservedly in my view) a good bit of favorable notice in this year’s Ex Machina. Here, her performance is restrained but powerful in scene after scene. She also has solid chemistry with Kit Harrington, as they portray a couple who are very connected on both an intellectual and physical level.

Vera’s memoir is over 600 pages long, and the act of condensing it into a two-hour movie leaves a number of rough edges. There are plot threads that aren’t well resolved, such as Vera’s time at Oxford, during which she must face the usual period disapproval of a woman pursuing a higher education. Similarly, the early scenes in the movie, showing the happier pre-war times that Vera and the various men in her life experienced, lack much focus. It’s only when the war starts that Testament of Youth finds its footing.

Testament of Youth is the rare film about war in which the war itself is not the most horrifying aspect. Although the movie doesn’t shirk away from showing the physical qualities, by far the worst effect is on those, like Vera, who are left behind. Behind an excellent performance by Vikander, nearly the entire horror plays out Win its effect on one remarkable woman and a few of those around her. World War I was sheer hell, but it’s a hell through which we see one woman emerge. Hopefully, it’s a hell and a movie that viewers won’t forget come end-of-the-year awards time.