What’s going on with the mystery tune everyone seems to know in Star Trek: Discovery season 3? Following the battle against Control in Star Trek: Discovery‘s season 2 finale, Michael Burnham led her ship and its crew through a wormhole into the 32nd century, keeping the Discovery’s sphere data safely away from Section 31’s murderous rogue AI program. Alas, arriving in the future has dealt the Discovery an entirely new hand filled with entirely new problems.

The biggest differences in the 32nd century are caused by the galaxy-wide event known as the Burn. A little over a century before Burnham’s arrival, almost every piece of dilithium in the galaxy abruptly went inert. With warp-capable ships relying exclusively on these precious crystals, the Burn was bad news for virtually everyone, but especially for the Federation, which has been forced to amalgamate with Starfleet and reduced to a mere shadow of its former self. The Burn remains a pressing mystery in Star Trek: Discovery season 3, with even Starfleet’s top man not sure where to point the finger of blame.

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Aside from the Burn, another curious mystery runs through Star Trek: Discovery season 3. Over the past several episodes, Michael has started to notice a certain piece of music recurring over and over again with diverse groups of people. Like an Ed Sheeran song, everyone seems to know this earworm without knowing quite where they learned it, setting Michael’s natural sense of intrigue on red alert. Here’s what the mysterious 32nd century chart-topper means for Star Trek: Discovery season 3.

The Discovery crew have been in the 32nd century for all of 5 minutes, and are psychologically still exhausted from crossing the time-space continuum. Michael Burnham, on the other hand, has been living in the future for an entire year. It’s strange, therefore, that she never came across this music until recently, when it cropped up three times in quick succession. Did Book never hum it in the shower? None of the couriers at the market? No street musician on the planets they visited? Burnham only began encountering the musical motif after reuniting with the Discovery and investigating the whereabouts of the Federation, which perhaps offers a vital clue as to the origins of the piece.

Burnham first hears the music played by Adira and remarks “that’s beautiful, what is it?” definitively confirming that she hasn’t heard it before. The same piece is then heard from the Barzan family on the Federation seed ship, and then various occupants of Federation HQ reveal they recognize it too. Adira, the seed ship caretakers, and Starfleet all have one thread in common – the Federation. Until now, Burnham had only been associating with outlaws, pirates and isolated planets – if she’s only now hearing the music, the tune must be intrinsically linked to the Federation.

In Star Trek: Discovery season 3, the Federation is in tatters. Only a comparative handful of the 350 member planets still remain, but both the Discovery and Admiral Vance remain optimistic that other Federation believers are out there somewhere, just waiting to be found. Only the lack of warp drive separates these potential allies from Federation HQ. It seems that Star Trek: Discovery is setting up its own Avengers: Endgame moment, where the lost planets of the Federation finally unite once again, proving that the spirit of cooperation and peace was never truly lost in the midst of adversity. Since only Federation members seem to know the music, the piece could be a rallying cry for the lost planets still hoping to rejoin their former brethren under one flag.

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Adira learned the tune from Gray, who likely received the melody from Senna Tal, the man who sent out the message of hope alerting Michael to the Federation‘s existence. The Barzan family on the seed ship had already found their way back to the Federation and were serving as guardians of an important resource, while all the folks in the hidden Federation base obviously returned to the fold too, one way or another. Everyone holding this piece of music in their memory has somehow returned home from the wilderness of a post-Burn galaxy. Consequently, the music could be some kind of call for former Federation members. A series of notes that, once heard, subconsciously leads those who still hope to be reunited with the Federation to their desired destination. If played loudly enough, and in full, the performance could return the union to its former glory.

As well as leading lost races back to the Federation, the music might also hold a deeper secret – namely, the cause of the Burn. During her investigations, Michael discovers that different people on the Federation base seem to know different parts of the song. Whilst it’s not unusual to recall the chorus to a classic anthem but mumble awkwardly through the verses, something deeper appears to be going on Star Trek: Discovery. When the Federation comes together and all the pieces are heard, the full song will be played and might reveal a long-hidden secret. And what could be more secret-worthy than the cause of the Burn?

This would fit perfectly with Star Trek: Discovery‘s “parts of a whole” theme. The Federation’s member planets are individual species who come together to form a stronger force. As Burnham and Saru point out to Admiral Vance, the same is true of the Discovery’s crew. It would be a fitting ending for Star Trek: Discovery season 3 if the final, finished composition unraveled the mystery of the Burn, with the notes perhaps spelling out coordinates that lead to the pesky villains who turned everyone’s dilithium crystals into desk ornaments in the first place. Again, this would continue Star Trek: Discovery‘s central message of strength in unity, and it’s only logical that whoever originally might’ve uncovered the cause of the Burn would encode the information and then split the song into separate pieces for protection.

Star Trek: Discovery season 3‘s “Die Trying” episode sees Burnham desperately trying to prove the Discovery’s worth to Starfleet to avoid crew members being reassigned or the ship placed under new command, and she succeeded by completing the mission to retrieve the Federation’s lost seed ship. While it’s obvious that the Discovery’s spore drive will be invaluable in a warp-less galaxy, it’s not yet clear how the ship can be of service. Perhaps the Discovery’s greatest contribution will be to zip around spreading this mysterious song, bringing more old friends into contact, and picking up new sections of music along the way. Without warp, this process might’ve taken Vance and his people centuries. The Discovery should be able to get the job done just in time for season 4.

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