“555” is a slow-tempo song with elements of ‘80s synth-wave. The song is about a loss of hope and experiencing frustration from the undesired outcomes in life, despite living how one believes they should.

The song begins with poppy synth effects and strong claps, backed by a signature ‘80s new wave synth-bass that produce a soundscape juxtaposed against the song’s despairing message. The song builds into an anthemic chorus reminiscent of such '80s acts as U2. In an October 2019 interview with Guitar.com, singer Adkins reflects on his expectation of the song’s reactions from listeners:

I was hoping people would say: ‘Fuck, what did I just hear?’ I was hoping it was too weird. 

The sound and subject matter of “555” conform to Jimmy Eat World’s recurring theme of a plea for acceptance that is seen throughout their discography, as Adkins describes in an October 2019 Kerrang! (UK) interview:

So the concept behind ‘555’ is basically feeling frustration that your prayers, for lack of a better word, are going to an uncaring universe. Like, ‘I’m doing everything right. Why can’t I get a win?’ There’s no hope in that song…… I feel like it’s a struggle for acceptance. You’re not going to get anywhere unless you honestly accept the reality of where you’re at. If you can take that step, things seem a little less scary and hopeless. And that’s it, but it’s still super hard.

The song’s title alludes to the service number advertised by the Ghostbusters from the 1984 film, as Adkins reveals in an October 2019 Kerrang! (UK) interview:

In American film, television or video games, when you need a fake phone number, those are the first three digits, because they don’t go anywhere. I remember watching Ghostbusters as a kid, that was the number to call on their commercial, and I remember trying it.

A music video for the song was released a day after the album’s release with a sci-fi inspired concept:

So ‘555’ sees me cast as a galactic evil master, overseeing an army of cloned species doing my bidding – this is the only life they know, joining me in song in this post-apocalyptic dystopia.

— Jim Adkins via press release (October 2019)