girl im gonna need you to elaborate on the fame is a gun x catherine standish thing bc im fascinated
thank you so much for asking anon i looooooove talking about slow horses and i've come armed with gifs. my answer probably relies more on fanon vibes from the show than i care to examine (i have not read all of the books) but to begin with, let us remind ourselves of some of the important things about catherine standish: she does not quit, she keeps coming back to objectively not good situations, she unfortunately likes being in on the action, and she is ultimately having a lot of fun, even when guns are being pulled on her. also, she thinks well on her feet, and she's very funny in a wry kinda way.
all these traits set her up to have conflict with two of our show's main antagonists (and my primary slow horses ships), jackson lamb and diana taverner, which is why it is important to remember that "fame is a gun" is an apostrophic song, directed at an unknown "you" questioning the speaker's desire:
what we know about catherine standish's history in the service is that she was absolutely devoted to charles partner, who supported her through her alcoholism, and jackson lamb's continued needling of her about it is one of their core relationship dynamics. catherine, as a result of tragedy, cleaned up her act; jackson, instigating that same tragedy, fell into a stinking (literal) pit of despair. her clean, calm, unassuming demeanor really does get at him ("provoke you with my tone of innocence")! they have interpreted this tragedy in radically divergent ways, not the least because of the power differential created by the information withholding inherent to the partner op. catherine's arrival at slough house occurred at a moment of profound self-searching ("tell me who i am") and heartbreak, and she needed the rupture and re-formation that her work at slough house provided ("it was the only way to mend my broken heart"), but she does sometimes miss being close to the heart of the action the way it was when she was at partner's side, much like how she is endlessly glad to no longer be an active alcoholic but also has to work every day to put that desire aside ("it never was enough, i always wanted more").
skipping ahead to fame is a gun verse 2, by the time we meet catherine, it's clear that she is both entirely used to jackson's needling and also beginning to chafe at it. all those shots of her turning away from his whiskey! all the barely suppressed eye rolls! ("and when you shame me"). the same thing is going on with diana, if we want to look at it through that lens: diana sees catherine's alcoholism and devotion to partner as something to use against her, and catherine's refusal to play the game is infuriating to diana - but also sexy! see me in the chat for fic recs!
so therefore, even in season 1, look at how eager she is to be of use during the hassan kidnapping! watch out, she's got a gun! ("it makes me want it more")
it is time for another period of growth and change, but she cannot admit that she wants it to diana taverner (or indeed anyone else):
by season 2, she's throwing herself into playing chess with russian spies despite not really knowing what she is getting herself into. ("i point it blind"). by season 3, she's letting herself be kidnapped for the greater good ("crash and burn"). she is having fun, even when in mortal peril, but also she can't quite cope with how it makes her feel. it's an exposure of sorts, a way of being that she herself hasn't seen in a long time, and which jackson and diana are always somewhat flabbergasted by ("you got a front row seat" - is the you here herself, or her bosses?). that push/pull is so delicious to me, and it keeps playing out over and over again, which is why i love this post made when season 5 was coming out:
something something the taste of the glamorous life!!!!!
finally, the bridge and final chorus:
in season 4, she helps river despite it all and by the end she comes back to the service, because at the end of the day she loves these freaks! she obviously loves the kids (river and shirley most of all), but she also loves jackson, and she can't stand to see him in pain and alone without her comforting touch!!!!! and i think there's a case to be made that she loves diana! she wants to keep tasting that glamorous life!!!!