Treat Williams did not receive an Oscar nomination, despite being nominated for an Independent Spirit Award, for portraying Arnold Friend in Smooth Talk.
The most concrete danger comes in the form of Treat Williams playing an older man, Arnold Friend who rides around in a convertible with his name plastered on the side. Although he isn't truly important to the film until just before a full hour in, we briefly see Williams as we follow Dern's Connie as she's going around town flirting, though not really quite sure herself when it comes to her precise decisions, but one of her interactions does briefly lead her to interact briefly with Williams's "Friend". Williams doesn't necessarily make an impact majorly one way or another as his character notes "I'm watching you" to Dern's Connie, though Williams delivery could be inappropriate joking, sleazy, or creepy, however his appearance is merely a brief establishment of the character. A character who returns to the focal point of the last act of the piece, as Connie is home alone when Friend, and another man appear on her front door in broad daylight. This sequence is very much what takes the film to another level, as it is the purest element of the adaptation of the short story the film is based on and where Williams's performance is the essential facet to the success of the entirety of the overall film. Williams's performance is one of those performances where an actor has a mastery of the material where the brilliance of his work is just how easy he makes it all seem. Because there's nothing easy about the role that would be so easy to fall into over the top cliche, or fail to reach the true insidiousness of the character. Williams avoids that but he goes one step beyond because what he manages to do is be both supernatural yet also absolutely real, which is quite the disturbing trick to pull off.
Initially Williams does seem just a man passing by, where the danger and potential threat bubbles just beneath. As he introduces himself as watching you, and going for a drive, Williams again brings a jovial quality, that he may just be a man inappropriately joking with a young girl, but it won't go further than that. However Williams's delivery of certain words like how he emphasizes and twists to "go for a ride" with sudden euphemism alluding to a disgusting lust of his own that we know that Friend isn't there just to joke around. As the conversation continues, which Connie goes from being intrigued by to terrified by moment to moment, Williams brings this supernatural quality, as he almost seems an embodiment of the devil with this sly smile as he begins to tell Connie exactly what she will do and exactly how much he knows. Williams's smile speaks to anything but happiness or concern for Connie, as the intention behind that smile always is ever present in the viewer's mind. Williams has the titular smooth talk where Williams's confidence is overpowering in a rather disturbing way, because you can entirely see where he would be successful in the way he does intrigue Connie. Williams's presentation of a simple charm, though elements of his performance would theoretically be potentially charismatic, though it's hard to speak of charm in such a situation, there is also an almost omnipresent element within that charisma. When Friend starts to talk about Connie's family being at a barbecue with exact details about what they are doing, Williams makes Friend almost otherworldly in the command of his words where everything he says seems to cut so deeply into Connie's consciousness, and Williams performs it all with such eerie magnetism.
But as much as Williams makes him the devil, he also makes him the skeevy man he is, who is disturbingly capable in this sickening arena. When he continues to speak to Connie and notes that they'll be "lovers", Williams still speaks with that same easy confidence of broaching the subject, forcing the notion on Connie but with the accentuating in the edges of the line and in his eyes the very clear lustful motivation behind Friend. Although at a certain moment, when his buddy in the car makes a noise, there is a change in the approach and the awful humanity becomes all the more evident. When Williams performs the verbal attacks on the other man, his performance suddenly loses any ethereal quality, and suddenly he's just a very scary man telling his accomplice to stop screwing him with his plan. The immediacy of the viciousness in his delivery Williams makes Friend that much more dangerous because he becomes truly unpredictable. It twists the rest of his performance further as he returns to his calmer voice with his urging towards Connie to let him in and making veiled threats of how things like a screen door won't keep him back. Williams's work becomes that much more oppressive with every word you see the man offering himself but also within every delivery creating the sense of the very real menace that exists making it only a horrid inevitability that Connie will eventually go with him. Williams delivers a terrifying performance here, one that is in broad daylight, with never any on screen violence yet it is one of the most oppressive and menacing performances you'll see. As Williams makes it so, by making it seem so easy in the way he is captivating, where we see him both as a demon from hell where nothing escapes his sight, however never is he less than real in creating the most disturbing of human behaviors.