After Eternals launched to Disney+, it paved the way in introducing us to a bigger Marvel Universe that will focus on cosmic beings. It teases a lot of potential future for the Marvel characters including Dane Whitman.
Game of Thrones actor Kit Harrington took a new swordsman role in the MCU. Dane Whitman, who is a love interest of Gemma Chan’s Sersi, seems to have a dark secret that was buried for centuries. In the post-credits scene of the film, Whitman is anxious about opening a box that is later revealed as the Ebony Blade.
Marvel fans speculate that Dane Whitman isn’t just a side character for the Eternal film. Instead, it’s Marvel’s subtle way of introducing ‘The Black Knight’ in the Marvel Cinematic Universe.
In the comics, the Ebony Blade was a magical blade forged from the starstone meteorite. It can cut through any object and can also deflect magic. But the sword also has a curse, making its wielder develop a thirst for violence and death. The original wielder of the Ebony Blade in the comics is Dane Whitman, who got it from his ancestor ‘Sir Percy; who forged the blade alongside Merlin.
In an interview with Zoe Ball Breakfast Show, Harrington discussed his future as Dane Whitman in the future of the MCU. Stating that he is ‘hoping’ that the MCU would continue to explore Whitman’s history. But as of now, Harrington states that he ‘has no idea’ yet about its future.
"No, not that I know of. It sounds like a very political answer. It’s exciting for me. The last film, as anyone who all have seen, it kind of sets an idea up that I might go further, so I’m hoping. But I think whenever you’re answering questions about these things, people point at you and say ‘liar’ as if you know more than other people, I have no idea. I genuinely don’t. I’m waiting for a call on it at some point."
Now, it's likely impossible that the MCU would cast a well-known actor for just a side character, and introducing him as Dane Whitman will definitely make it worthwhile for the future films of the MCU to play with his character.
We can only assume that Dane Whitman will be back either on Eternals’ sequel or we can see him as another side character for Marvel’s future films and TV shows. If the MCU really wants to explore his history and introduce him as a key character, he might even get his own show.