When it comes to violence, there's very specific kind of superficiality at-hand in even the best and smartest movies that usually doesn't apply in comics. This is maybe best exemplified in the image Jesse talked about in his Powerful Panels post, the back-of-the-head exit-wound, the kind of violent image that can pretty much only be done in comics.
Explicitly, there's a cap on how much and how gruesome violence can be in a movie. Violence can be shown and violence can be shown realistically to a certain point and that certain point often stops at the all-too-real exit wound. There's a jagged kind of beauty to the slow-motion violence of Peckinpah or the infamous shoot-out finale of Arthur Penn's Bonnie & Clyde, but it still works within the constraints of not making the violence too-much, too-real, as to remind viewers too much of their innate fragility and morality.
Psychologically too, there's probably something in our brains that makes it more immediately rewarding and gratifying to see images related to entrance (or let's be obvious about it: penetration) than to exit. Also, damage to the face is especially disturbing because that damage alters our most "identifiable" feature and the blowing-out of the brains strips the person or character of their capacity for personal thought, another thing we hold dear and maintain, makes us an individual.
There's also a kind of conventional film grammar violation when the back of a person's head is shown. Movies have certainly shied away from the old Hollywood era of constant close-ups, but films are still about faces, even when they're shown punched up with bullets. Rarely ever will a movie reveal a bullet's exit from Otomo's angle, in part because it's particularly gruesome and also logistically, it's a rather hard thing to pull off, even with special effects. And so, doing what Otomo did in that panel violates the rule of how far violence can go and the more immediate rule of conventional dramatic impact rooted in audience identification with the character.
Think of how often older Westerns--the ones that actually are racist, not the ones people misread as racist--often show the Native American characters from the back; it's a trick done in jingoistic World War II movies as well. As a rejection and attempt to complicated film grammar,New German cinema director Werner Herzog, when questioned on placing actress Isabelle Adjani away from the camera for a particularly emotional scene, simply said: "I don't want to see the actress cry. I want to see the audience cry." A rejection of Hollywood and its melodramatic techniques.
To show the back of a character's head--as Herzog does--and to show a bullet exiting the head--as Otomo does--is something of an affront to many things we hold dear about self and identity. The exit-wound head-shot is gruesome and scary and because it's so often eschewed in films, it's shocking. This is of course, what that scene in Akira is all about, Kaneda's shocked at Kei's ability for violence, Kei shocked at her own capacity for violence, and it's all driven home in a frame that highlights the shooting precisely by not looking like every other "guy being shot" comic frame. The simple but for some reason almost-taboo act of reversing the angle does the trick.
In this iconic image from Frank Miller and Geoff Darrow's Hard Boiled, the head shot's taken to outrageous extremes but still, there's a kind of core, gut-level shock of emotion and recognition that comes with staring at that frame. Only a few moments into staring at it does one realize that it's the back of the head and then all the gory details set-in. Sure, it's fun and delightfully over the top, but it also has the same effect of seeing a particularly mangled deer carcass on the side of the road. You're okay when it's just a dead lump, but if like, a lot of blood or some rib-cage sticks out, it's way more disturbing. Darrow's picture reminds any thoughtful comics reader that flesh can be torn open quite easily, that our brains will drip, and our teeth just sit dumbly in our mouths. Darrow also adds a kind of meta level to the image, as the viewer is the one Nixon speaks to, through the hole in the guy's head and the "Sorry, I'm late." line is a kind of apology to readers that waited much too long for the oft-delayed third issue of the series.
Kyle Baker's cover to Special Forces #2 is an obvious homage to Darrow's classic image but also a kind of one-upping in terms of shock value. The head with the gun blast hole in it is Mickey Mouse's and while this has less of the immediate reality that we're flesh and bone feeling to it, it fucks with us on the level of this iconic hero of our childhood's just been blown up. Baker even flirts with Darrow's highly-rendered, mortality-realizing detail by giving us the blood edges around the blast but nothing more, presumably because Mickey's a cartoon character.
In a return to relative subtlety, there's this image from issue #3 of Joe Kubert's Sgt. Rock: The Prophecy series. Sergeant Rock has been captured by Nazis who quickly realize conventional interrogation isn't going to work, and so, in hopes to get him to talk, he's smacked with the butt of a rifle in one frame and then, held down and punched in the next few. In the second to last image on the page, Kubert reverses the "angle" as Rock's being pummeled and reveals a rather disturbing gash--the result of the rifle butt--on the back of Rock's head. Kubert does the odd but somehow perfect effect of covering the light red specks of blood with a violent slash of black ink, drops of it splattered down to Rock's neck. The black ink doesn't make any realistic sense here, but it's the perfect choice for jarring the reader into the reality of Rock's current situation. While analogous in some ways to the Otomo image, it's also significantly more self-conscious and over-the-top than Otomo and in that sense, has some connection to Darrow and Baker's images.
While I began this piece with a rather disparaging discussion of film and the conventionality of film grammar, I'd like to end it by looking at what may be the film equivalent of comics' head shots: blood on the the lens. Realistically, it's pretty impossible for a movie to show an exit wound without the aid of CGI, but the odd effect of having some blood splatter onto the camera might be the closest thing. It's an easy trick that gives the illusion of a bullet's motion and impact and like Darrow, Baker, and Kubert, because the self-conscious act is so over the top, it actually makes image more emotional and more real, even as it calls attention to the artificiality of itself. A particularly fascinating use of this effect is in Andrew Dominik's The Assassination of Jesse James by the Coward Robert Ford.
The scene's crucial to the character of Robert Ford because it is the first person he kills and will in many ways, mirrors his murder of Jesse later. The blood on the lens turns the scene a little surreal and marks it as particularly significant or transcendent for the character.