Just because it's a post-apocalyptic show in which society has been stripped down to its bare,sex videos irani feral bones, doesn't mean The Last of Uscan't also feature the finer things in life.

Music, for instance.

From the very first episode, Craig Mazin and Neil Druckmann's HBO adaptation of the Naughty Dog game uses music in a key way, with Depeche Mode's "Never Let Me Down Again" setting an ominous tone for what lies ahead. Episode 3 closes this musical loop with the love story of Bill and Frank and its use of another key song: Linda Ronstadt's Grammy-nominated, 1970 ballad "Long Long Time," from her second album Silk Purse. In fact, the episode is even named for the song.

How does Linda Ronstadt's "Long Long Time" feature in episode 3?

Not long after the Cordyceps pandemic outbreak, survivalist Bill (Nick Offerman) discovers an uninfected stranger, Frank (Murray Bartlett), caught in one of the traps he's set outside his fortified home town. After reluctantly helping Frank out of the hole and giving him a fine meal of rabbit and Beaujolais in his home, Frank gleefully but courteously wanders over to Bill's piano and starts flipping through the stash of sheet music. Ditching several unappetising composers, he settles on The Best of Linda Ronstadt.

"Thisis you," says Frank, flipping through the book and sitting down at the keys. "Oh my God, that's my favourite."

He begins to play and sing along to "Long Long Time" before Bill quickly takes over in protest of Frank's jaunty performance, singing the opening lines in a gruff, pained, but reverent voice.

"Love will abide, take things in stride,
Sounds like good advice but there's no one at my side.
And time washes clean, love's wounds unseen.
That's what someone told me but I don't know what it means.

'Cause I've done everything I know to try and make you mine,
And I think I'm gonna love you for a long, long time."

Ronstadt's song prompts Frank to gauge and confirm Bill's sexuality, as moments later, the two of them share a passionate kiss that starts a decades long relationship. In this sense, "Long Long Time" is the catalyst for their relationship and everything that follows.

"We had this idea that Bill and Frank would connect over a song. That would be the thing that would essentially lead Frank to feel differently about Bill, to not just go 'oh, I see what's going on with this guy,' but also to want him," director Craig Mazin said on HBO's The Last of Uspodcast. Mazin got the idea for the song from his friend, Broadway stalwart Seth Rudetsky, who hosts Sirius/XM Satellite Radio's On Broadwayshow.

"It was an interesting rotation of expectations. You might think Frank feels like the kind of guy that would be really good at the piano and have a beautiful voice, and he's absolute shit at piano — by the way, Murray Bartley is great at the piano and has an excellent voice, which is why he was so funny doing an impression of a terrible player with a terrible voice."

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Written by Gary White, Ronstadt's song actually concerns unrequited love, but in The Last of Us, Bill stops before the second and third verses, which include much more explicitly pained lyrics about "a love that never was." So, by cutting off the song here, the show keeps the burgeoning romance on a positive track, avoiding the ruin Ronstadt sung about.

What's the significance of "Long Long Time" playing at the end?

After a moving episode that tracks the life Bill and Frank share, from their first meeting to their deaths not long before the arrival of Joel (Pedro Pascal) and Ellie (Bella Ramsey), things end on a suitably poignant note.

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After Joel has read the letter Bill's left for him and they've topped up on supplies, Joel and Ellie set out for the road in Bill's truck. In the glove box, Ellie finds a tape with "mix for Bill" written on the side, and she slots it into the car's player over Joel's objections. But as soon as the music starts playing he changes his mind.

"Oh no, wait," he says. "No, leave it. Leave it, this is good, this is Linda Ronstadt."

As they drive away from the home Bill and Frank shared for decades, we hear the original version of "Long Long Time", the song Bill and Frank played for each other on the piano all those years ago. It's a fitting reminder of how much Joel and Bill have in common (something Bill underlines in his letter), but also a poignant throwback to the start of Bill and Frank's relationship.

And it's not the only important use of music in the episode either.

The Last of Usis now streaming on HBO Maxwith new episodes airing weekly on Sunday nights on HBO.