What Illness Did Frank Have In ‘The Last Of Us?’

(Spoilers for The Last Of Us will be found below.)

HBO’s The Last of Us deviated from its source material in a big way to tell a heartbreaking love story set to the backdrop of a fungal apocalypse in episode three’s “Long Long Time.” And, while we’re all still recovering from that emotionally devastating ending, fans were left with some questions about show-invented storylines for secondary game characters Bill (played by Nick Offerman here) and Frank (Murray Bartlett).

After going on a quick supply run with Joel (Pedro Pascal) and Ellie (Bella Ramsey), audiences were treated to a flashback that introduced Offerman’s eccentric survivalist building his own Infected-free Utopia in a small town somewhere in Northern Massachusetts. Like his videogame counterpart, Bill managed to evade a military-enforced evacuation and use his wealth of knowledge and life experience to create a safe haven for himself. He eventually shared it with Frank, a drifter who became his life partner, but that’s where the similarities between the game and show end.

Gamers never met Frank — while he was still alive, anyway — learning that he left Bill over a disagreement, became infected, and chose to kill himself rather than be turned into a fungal puppet. His relationship with Bill in the game was never really fleshed out although his death clearly affected the stoic loner.

“Long Long Time” expanded their love story, dedicating nearly an entire episode to building a moving Queer romance that has a bittersweet ending but also, a happy one, as far as zombie apocalypses go. The show spent time with the pair as they met, fell in love, built a home, and grew old together. After a significant time jump, the episode ends with the pair deciding to die together, a choice Frank initially makes because he seems to be suffering from a debilitating illness that’s greatly affected his quality of life. Naturally, fans were curious as to exactly what Frank was sick with and, thanks to a recent interview with showrunner Craig Mazin, we’ve got a better idea.

In a chat hosted by the official The Last Of Us podcast, Mazin revealed Frank had either MS (multiple sclerosis) or ALS (amyotrophic lateral sclerosis, also known as motor neurone disease), though he admitted the writers didn’t want to assign a specific label to the illness. There are enough hints throughout the episode to prove Frank was living with either MS or ALS though, including his later wheelchair-bound state and weight loss. Both diseases damage a person’s nervous system which can lead to problems with movement and speech — hence why Frank could no longer walk on his own or paint like he used to. Frank also alludes to the fact that, even if the fungal outbreak never happened, there still wouldn’t be a way to fight his illness because the world before hadn’t found a cure.

“This happens, it happens so commonly and yet, so rarely,” Mazin said of Frank’s deteriorating state. “As people get older on screen, they tend to be fully healthy until the heart attack staggers them out of nowhere. That does happen but for the majority of people, there is a decline. We thought it was really interesting to think, ‘Look, Bill is older and Frank can literally run circles around him, he’s healthier, Bill gets shot.’ And then we jump ahead a number of years and it’s Frank who’s been brought low by this disease and there’s nothing they can do about it. But you can see how Bill is doing his best to caretake Frank the way that Frank would caretake Bill.”