Netflix's Emmy-winning House of Cards is supposedly the story of Frank Underwood - the tale of how Kevin Spacey's ruthless Chief Whip uses all of his cunning (and a few dirty tricks) to rise to the most powerful position in US politics.
But if you've been (binge-)watching the show since it launched in 2013, you'll know there's another character even more nuanced and complex than Frank - his lady wife, Claire.
Brought to brilliant, terrifying life by Robin Wright - who won a Golden Globe for her performance - here are 8 reasons why Claire is the First Lady of television - and easily the best thing about House of Cards.
1. She's a (mostly) original creation
House of Cards is based on a BBC series of the same name - and while Frank's counterpart Francis Urquhart is every bit as devious as his American cousin, there's not really a Claire equivalent on the show.
Francis's wife Elizabeth (played by Diane Fletcher) is without question intelligent, self-motivated, even callous, but she's more of a Lady Macbeth figure, lurking on the sidelines and provoking her husband into action.
What to Read Next
Claire is almost an entirely different character - a creation entirely of HoC showrunner Beau Willimon, rather than original author Michael Dobbs or writer Andrew Davies.
2. She has it tough as a woman in a man's world
In 2016, we've got Hillary running for President, but politics in the United States has long been a male-dominated sphere and House of Cards isn't afraid to expose - and denounce - those old attitudes.
From the show's own Presidential frontrunner Heather Dunbar (Elizabeth Marvel) to Frank's replacement as Whip, Jackie Sharp (Molly Parker), the women of HoC have to work twice as hard to succeed, and combat chauvinism in Washington.
Claire has it worst of all - as First Lady, her husband expects her to be mere decoration on his arm. But her own fierce ambition was what drove her to eventually leave Frank at the close of the third season.
3. She's nobody's victim
Claire was sexually assaulted at college by a classmate - Dalton McGinnis (Peter Bradbury) - but got her revenge years later when the now three-star general came back into her life.
Exposing McGinnis as a rapist on national television, Claire sent her attacker to prison for 40 years, sparking a wider discussion about sexual violence in the US military - and all of this while Frank impotently fumed.
4. She never loses her cool
Speaking of which… it was when Frank's anger got the better of him in season three's finale, leading him to physically attack Claire, that she knew she had to get out of their toxic marriage once and for all.
To lose your temper is to admit that your enemy has got to you - it's a sign of weakness.
Part of what makes Claire so electrifying - and Wright's performance so compelling - is just what a cool customer she is. The First Lady eliminates problems - and people - with icy efficiency, never a hair out of place.
5. She makes being bad look pretty good
...and while we're on the subject of hair, Claire never looks anything less than amazing - blonde or brunette - and she's always dressed to impress.
Vanity Fair has written articles on how to copy Claire's best 'Power Looks', The Independent has hailed her "impeccable style", while The Observer put her "on a par with Jackie Kennedy".
Fictional or not, there's no questioning Claire's status as a bona-fide fashion icon.
6. She's Frank's greatest weakness
Smart, pragmatic, merciless, with a seriously warped moral compass, there's not very much that can hurt Frank Underwood, especially with the powers of the Presidency at his disposal.
Claire is his greatest - and perhaps only - weakness. She has the dirt on Francis - knowledge, or at least strong suspicion, of his entire catalogue of crimes - and she's every bit as smart as he is.
"She's a very strong and independent woman that's capable of anything," Doug Stamper actor Michael Kelly told DS. "So yeah, she's a formidable foe to anyone."
7. She's not just an emotionless super-villain
Frank might be powerful, but he's a bit of a cold fish - despite his frequent conversations with the audience, only very rarely are we allowed to see the real Frank, a man with doubts and anxieties.
By contrast, House of Cards has shown us many different sides of Claire - she can be hard-hearted and cruel, but she also had genuine feelings for her ill-fated photographer boyfriend Adam Galloway (Ben Daniels) and was visibly distressed by the suicide of LGBT activist Michael Corrigan (Christian Camargo).
8. She's not too proud to learn from the best
It's not a massive spoiler to say that season four of House of Cards will deal with Claire and Frank's ongoing feud. And while she's got a few advantages over her husband, Claire's not afraid to take pointers from him either.
Whether he'd admit it or not, Frank's aid Stamper is pivotal to his operation - and this season, Claire hires a 'Lady Stamper' all her own in the form of Neve Campbell's political strategist Leann Harvey.
Make no mistake, the war of the Underwoods is on - and the winner is by no means a foregone conclusion.
House of Cards season 4 is available to stream exclusively on Netflix from Friday, March 4.
