In The Crown, season 4, Diana makes such a good impression on Prince Philip that he likes her immediately. Lady Diana Spencer was only nineteen when she visited Balmoral Castle, where her introduction to the royal family was dubbed a “triumph” by Charles — speaking to Camilla — in The Crown season 4, episode 2, “The Balmoral Test.” While it’s true that the real Diana visited Balmoral Castle in November of 1980 and Prince Philip liked her from the beginning, “The Balmoral Test” – like much of The Crown – is heavily dramatized. The real Diana and Philip had a complicated relationship that grew from cordial to deeply affectionate, but later evolved into mutual hatred.
When Diana joined the royal family by marrying Prince Charles, Philip took Diana under his wing. But Philip became infuriated with his entire family when Charles and Diana's marriage began breaking down just a few short years after their "fairytale" wedding. Diana, on the other hand, was hurt by Philip’s criticism and hated him for it. By the time Diana had officially divorced Charles, she and Philip disliked each other so much that it’s perplexing how or why they got along in the first place — but The Crown wasn’t necessarily wrong to depict the two royals developing a kinship in their first meeting.
When Philip meets Diana in “The Balmoral Test,” it’s on the occasion of a royal family weekend at Balmoral Castle. Philip and Diana are hunting a wounded stag (a rather on-the-nose metaphor for the episode) when Diana impresses Philip with her humor, charm, and hunting knowledge and he is beguiled by the conundrum of her meekness and self-assuredness – she’s not afraid to tell the Duke of Edinburgh that he’s wrong, but bashfully deflects the praise she receives for being right. And while the hunt for the imperial stag was invented for the sake of drama, The Crown accurately depicts Philip and Diana sharing a camaraderie in their “outsider” status.
According to Tobias Menzies, the actor who portrays Philip, “[Diana’s] another outsider, a position that he obviously has been in. Maybe he has some kind of appreciation for the challenges that she's going through” [via People]. In The Crown, Philip is also drawn to Diana’s beauty and coyness, but Menzies believes that Philip “ends up underestimating her actually, which is slightly paternal blindness, arguably sexism.” In both the show and reality, Philip took the role of a father figure to Diana, helping her adjust to royal life and being called "Dearest Pa" by Diana in letters, but due to Charles and Diana's divorce and Philip's unwillingness to fully acknowledge Diana's suffering, their friendship did not last.
Diana's unhappiness in her marriage and Philip’s displeasure at the prospect of her divorce will more than likely affect their relationship the final two seasons of The Crown. The dissolution of their bond will be heartbreaking to watch, since the two likable loners had become an unlikely pair, with newcomer to the royal family (and show), Diana, exchanging friendly winks and smiles with Philip in season 4 of The Crown. But like so many other relationships, fictional and real, the bitterest rivalries often develop out of the closest companionships.