House of Cards is a television political thriller series created by Beau Willimon. It is an adaptation of Michael Dobbs' 1989 novel of the same name and the 1990 British miniseries by Andrew Davies, which also adapted the novel.
The show revolves around Frank Underwood (Kevin Spacey), a cunning Democrat from South Carolina's 5th congressional district who, after being rejected for the role of Secretary of State, plots an evil scheme to take charge with the assistance of his similarly manipulative wife, Claire Underwood (Robin Wright).
The series addresses issues like manipulation, ambition, betrayal, and ruthless pursuit of political power.
In the final episodes of House of Cards, Claire pulls off a bold political maneuver—publicly announcing her pregnancy. The revelation sways public opinion, helping her avoid impeachment. But her grip on power is threatened when Doug Stamper begins leaking Frank’s audio diary to the press.
To protect her position, Claire publicly distances herself from Frank and fabricates an international crisis.
As tensions rise, Claire receives a disturbing gift from Doug and prepares for a final confrontation—one that will determine who controls the legacy Frank left behind.
House of Cards ending: The reason behind Doug Stamper’s decision to kill Frank Underwood

One of the finale’s most unexpected twists is the revelation that Doug Stamper, Frank’s fiercely loyal right-hand man, who continued to defend him even after his death was actually the one who killed him.
However, this twist aligns with Doug’s character development throughout the season. With Frank gone, Doug becomes obsessed with preserving his legacy as a great leader and punishing Claire, whom he blames for contributing to Frank’s downfall.
After the season 5 finale, in which Frank threatened to kill Claire if she didn’t grant him a pardon, Doug realized Frank was serious and prepared to act on that threat. Desperate, Doug secretly gave Frank a fatal liver medication overdose to prevent him from killing Claire and becoming a murderer.
The motivation behind Claire’s decision to kill Doug

Doug Stamper is someone who knows all the dark secrets, he worked alongside Frank Underwood for two decades, playing a key role in many of his most sinister and illegal operations.
In one of his final moves before his death in House of Cards, Frank revised his will to leave everything to Doug, including a USB drive containing his audio diary knowing Doug could use it to take down Claire.
After Claire orchestrates the deaths of Jane Davis, Cathy Durant, and Tom Hammerschmidt, she is aware that Doug is the last living connection to the Underwood administration’s crimes. As long as he is alive, he poses a serious threat so he must be eliminated.
Reasons Claire is expected to avoid punishment for Doug’s murder

Killing someone in the Oval Office may be the boldest crime either Frank or Claire has ever committed but it is clear that Claire is going to get away with it.
Colonel Flora is already under arrest in House of Cards, and Doug handed Claire a list of everyone involved in the plot to assassinate her, giving her the leverage to eliminate her remaining enemies, including Annette Shepherd.
Claire strategically left the letter opener on the desk and emotionally pushed Doug to the brink—a risky move, but one that worked in her favor. The injury on her neck serves as physical evidence that Doug attacked her, allowing her to claim self-defense.
In the eyes of the public and the law, it is the word of the President of the United States who also happens to be pregnant, against that of a dead man with a history of mental instability and a prior murder charge.
Claire also now holds Frank’s audio diary, which Doug never would have entrusted to anyone else, knowing it contained damaging truths that could tarnish Frank’s legacy. With that in her possession, her secrets are safe. For now, Claire has won.
The possibility of Claire launching a nuclear strike
With Doug out of the picture and the danger posed by both his knowledge and Frank’s audio diary eliminated, Claire no longer has a real need to maintain the distraction of the nuclear standoff.
Earlier, Claire admitted she never truly wanted to launch a nuclear strike. She will likely back down from the Syria threat perhaps by revealing the ICO leader is dead and work to ease tensions with Russia, aiming to de-escalate the crisis before it worsens.
Though Claire may back down from the nuclear threat now, she has shown she will go to great lengths to protect herself. With Doug’s evidence, she can silence her biggest rivals and secure her power but if cornered again, she might not hesitate to trigger a nuclear crisis.
Determining the father of Claire’s baby
To the American public, widowed President Hale appears to be expecting her late husband’s child but the reality is more complicated. In a conversation with her younger self, Claire admits there is a 50-50 chance that she is carrying a demon seed, suggesting she is uncertain whether the baby’s father is Frank or Tom Yates.
The true significance of Frank’s (and Claire’s) asides

One of the most surprising twists in House of Cards season 6 is the revelation that Frank Underwood’s frequent asides to the audience were actually excerpts from a secret audio diary he recorded throughout the series.
While it may seem unlikely that Frank would document a detailed confession of his villainous deeds knowing it could destroy him if discovered, it highlights just how deeply he trusted Doug Stamper, leaving the diary to his loyal right-hand man after his death.
This then leads to the question of whether Claire’s direct addresses to the audience also imply she kept an audio diary and if Doug’s occasional looks to the camera suggest he, too, recorded his inner thoughts.
The message House of Cards conveys about power and America
While some viewers might see House of Cards as depicting the American government being overtaken by unprecedented levels of deceit, corruption, and malice, the deeper message especially in season 6 is that what Frank and Claire did isn’t so unusual.
The series explores a subtler, more insidious form of tyranny, one that is harder to execute but also much more challenging to uncover and overcome.
In House of Cards finale, Mark Usher visits a frail Bill Shepherd, now dismissed and ranting about Claire. He warns that Annette plans to side with Claire. When Bill asks about the future, Mark says things don’t change, they just fade away.
Later, Bill Shepherd reflects on paintings from various eras, including Chardin’s The House of Cards, noting they all depict children waiting for the cards to fall.
This symbolizes the show's view of power as fragile and easily toppled. Frank saw his downfall coming but couldn’t stop it, and Claire’s reign seems doomed too, as keeping the house of cards intact is a nearly impossible task.
Interested viewers can watch all six seasons of House of Cards on Netflix.