I was sooooo super-worried about writing Arthur and Eames the first time I wrote them. I literally sent it off to a friend, like, “Is this any good? It’s terrible, isn’t it? Is it good? I bet it’s horrible. Do they just sound like John and Sherlock? Gah!”
I remember that my key to Eames at first was: take the first line of dialogue that came into my head for him and make it *more sarcastic.* So, like, my first Eames scene I ever wrote was when Mycroft hits him with the car and takes him to the interrogation room and originally Eames had some kind of bland line, I don’t even remember what it was, but I was like, “No, make it drier, what can you give him?” and it turned into his line about how dinner would have been more polite. Same with his line a little later about whether he can get some popcorn. Those were my two lines that I felt like made Eames not sound like John. I mean, I was writing a confrontation with Mycroft, I was worried about it being too much like ASiP.
These days I worry less about Eames, I feel like I have his voice better and so I no longer second-guess his lines of dialogue, strive to find something more flippant, but I think, just starting out, it helped unlock him for me. So that’s my word of advice for him: I think he should almost always be the one being droll-est. (Even though he’s also almost always the one being the most serious about everything underneath it all.)
Arthur terrified me for a while. The first time I went into Arthur’s head, I was like, “Ugh, I have no idea what I’m doing with you.” Remember back when I first fell for Inception and I was so in love with Eames? I still love Eames, but I have shifted my personal alliance to my Arthur, who I adore fiercely and I never want to leave his head. This is how I am. I avoided Sherlock’s head, too, and then it was *lovely* in there. I’m an idiot.
The key to Arthur for me: My Arthur swears a lot more than any other character on the page for me, ever. I have no idea why this is, but I feel like Arthur is just like that and I feel like once I embraced that Arthur flowed for me. I think it helps to keep Arthur feeling constantly exasperated. Everything is exhausting to Arthur because nothing is the way it’s supposed to be, damn it, he has to do everything himself, ugh. It’s kind of a Sherlockian sort of attitude but it’s a bit rougher-edged (Sherlock’s so posh, and Arthur dresses nice but I think he’s no aristocrat). Also, Arthur doesn’t share Sherlock’s penchant for dramatics. Arthur leaves that stuff to Eames. So I think that also helps keep Arthur from sounding too much like Sherlock (because otherwise my take on them is fairly similar, in that I write them both as enormous romantics who cover that up). Arthur’s the point, he’s not the star, he’s the one behind the scenes, and he’s fine with that. So Arthur’s going to put his head down and just got it done. He doesn’t talk as much as Sherlock does, unless it’s to Eames, and that’s just because, well, Eames is excellent at pressing Arthur’s buttons and getting him to talk.
I read a lot a lot a lot of Inceptionfic that helped me get their fanon done, and then those two really concrete steps really helped me, I think. And then once you can find a way in, I feel like then you’ve got them, or at least your version of them. I’m not entirely sure anymore that my Arthur sounds much like other people’s Arthurs, but I’m okay with that because he’s mine, and I love other people’s and I love mine and Eames loves all of them and we’re all happy together.
Someone told me that I once gave them advice for writing Sherlock and I said the most important thing was to know what you thought about him and as long as you were consistent with that, people would go along with you. I think that holds for all writing and so I’d say to listen to them and let them tell you the way. :-)
Hope this helps! I WELCOME ALL INCEPTION AUS, LET ME TELL YOU. ALL OF THEM.