'Star Trek: Discovery' Season 3 Ending Explained: What caused the Burn and what's next for the new Captain?

A closer look at the events of the 'Star Trek: Discovery' Season finale and what might be coming next for the ship and its crew
Bill Irwin as Su'Kal on 'Star Trek: Discovery' (CBS All Access)
Bill Irwin as Su'Kal on 'Star Trek: Discovery' (CBS All Access)

It took over a hundred years and a teleporting ship from the past to be able to figure out what caused the Burn, but at long last answers have been found, and the threat of a new Burn eliminated. With the Discovery's new Captain leading the charge, the universe's dilithium shortage is about to be a thing of the past.

Captain Michael Burnham (Sonequa Martin-Green) and the crew have managed to save the Federation in its most desperate hour. The only question is, what comes next? We take a closer look at the events of the revelatory season finale.

What caused the Burn?

Hannah Spear as Dr Iss on 'Star Trek: Discovery' (CBS)

In the last episode, it was revealed that Su'Kal (Bill Irwin) was responsible for causing the Burn, and in this episode, we get an explanation on how that happens. Hugh Culber (Wilson Cruz) explains that a genetic mutation caused Su'Kal to be born a polyploid — someone whose genetics alters based on the environment around him. Born on a planet filled with dilithium, Su'Kal's genes gave him a unique connection to dilithium, and through dilithium, subspace itself.

His sonic waves, especially, would be transmitted through subspace, which is how the Kelpian lullaby was transmitted through the universe — he must have resonated the tune through subspace, where it became a part of hundreds of cultures through the universe.

More importantly, the shock of seeing his mother's death caused a young Su'Kal to scream in horror, which, combined with his connection to dilithium sent a shock wave throughout the universe that caused an explosive reaction, causing the Burn.

Now that he's been removed from the Verubin Nebula, however, and the planet of dilithium, his connection has been broken — meaning that there's no chance of another Burn incident happening anytime soon.

The Discovery's New Captain

Sonequa Martin-Green as Captain Michael Burnham on Star Trek: Discovery (CBS)

Michael Burnham (Sonequa Martin-Green) is finally the Captain of the Discovery, which many fans feel is a moment that has been long overdue. It's been a long journey to the Captain's chair, and this season was especially challenging.

However, after almost single-handedly coming up with a plan to foil the Emerald Chain, taking out Osyraa and her operatives, and saving the ship in time to rescue those stranded in the Verubin Nebula, the crew and Admiral Vance (Oded Fehr) believe it's time that Burnham stepped up, especially since it's Burnham herself who pushed for understanding the Burn, which is what, ultimately, will save the Federation.

What comes next?

The Federation did not fall apart because of the Burn, but because they were unable to keep the United Planets connected in the aftermath. Thanks to the Discovery, however, they're not only able to finally explain what caused the Burn, but they can start reuniting the scattered planets.

Long-distance travel was all but impossible without dilithium, and with a planet full of the stuff, the Federation is now able to make long-distance travel a possibility again. The Discovery now has a new task — to get dilithium to planets that need it the most.

Crew changes

Still from 'Star Trek: Discovery' (CBS)

Not everything is fully resolved with the crew, however, on the ship, and there's a lot to deal with in the next season. Most pressing is the fact that Paul Stamets (Anthony Rapp) has still not forgiven Burnham for choosing to save the Federation before saving his husband, Culber, from radiation poisoning in the Verubin Nebula.

Stamets is barely able to fake a smile when Burnham is made captain, and given the fact that Booker (David Ajala) is now able to use the spore drive as well as Stamets, Stamets might not be sticking around for long.

In the meantime, Adira Tal (Blu del Barrio) has a quest of their own to deal with — to find a way to make their boyfriend, Gray Tal (Ian Alexander) corporeal in some way. Gray was able to be touched for the first time since his death while he was in the holodeck simulation that Su'Kal was trapped in — meaning that it may be possible for Gray to return if the Discovery's own holodeck can somehow be made portable.

It doesn't appear like the Discovery will be returning to the past any time soon, and they seem to have accepted their new home and new roles as heroes of the Federation in the 32nd Century — where they will continue to adventure when Season 4 comes around.

All episodes of 'Star Trek: Discovery' are now available to stream on CBS All Access.

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