麦可儿来到发现号，和众船员说到这一年的经历：由于空间站无法进行长距搜索，她成为了送货员，利用送货的经历，一边收集联邦的信息，一边等待与发现号的通信。之后她建议发现号回到地球，因为她从联邦一个废弃通信线路打听到地球一名名为塞纳·塔尔（Senna·Tal）的上将广播仍有联邦的人员存在。

阿迪拉无法想起她如何成为楚尔人共生体的宿主，也无法想起塞纳·塔尔的记忆。于是麦可儿建议回到楚尔人的母星来寻找解决方法。楚尔人已经退出联邦，十分欢迎现有的共生体回归家园，但无法接受人类成为共生体宿主，首席要求他们离开，而其中一派甚至试图让阿迪拉与共生体分离，一名叫“习”的护卫帮助她们来到楚尔人共生体的起源洞穴来试图重建阿迪拉与共生体的联系。

在塞纳提供的信息，发现号找到了星际联邦及舰队的总部，总部仍有大量尚存的星舰和一定的科技优势，但只能勉强维持并且与众多联邦成员星体失去联系。总部的上将万斯（Vance ）十分惊奇发现号的归来，但由于“管控”战争后星际联邦消除了所有关于发现号、“管控”系统的资料，导致无法核实发现号的身份，而且三十世纪的时间大战，导致十分恐惧有时间特工乘虚而入，所以对发现号的全员做了十分严格的审查，甚至想解散发现号的团队。

发现号进行了多项未来科技的改造，万斯上将安排了其他星舰支援成员行星的行程，但保留发现号作为快速机动部队，令萨鲁无法展现对联邦的忠心。此时布克的飞船独自来到联邦总部，带来了一条消息：他在几星期前在一个由翡翠链控制的星舰回收坟场发现了一些星舰的黑匣子可以帮助了解“大燃烧”事件的起源，但如果他不能及时回来就让飞船独自找回发现号，这意味着布克出事了。

布克突然收到他兄弟基希姆（Kyheem）在母星奎寄安（Kewjian）发来的信号。基希姆的家族为了获得能驱除母星上的蝗虫的驱虫剂而与翡翠链合作以提供迷幻虫，而翡翠链是一个由安多利人和奥利安人（Orion）组成，由奥利安人欧萨拉（Osyraa）领导的联盟，通过向没达到曲速文明的星球提供科技来达到对星球的控制，布克就是不满基希姆与他们的合作而离开母星。

镜像菲莉帕出现越来越严重的病症，医官休和联邦的研究员认为这是因为镜像菲莉帕是从镜像宇宙穿越而来，并且由向主世界穿越900多年，导致身体的原子状态极度不稳定。发现号的球体数据让电脑给出让镜像菲莉帕到丹努斯五号星一趟的方案，镜像菲莉帕和麦可儿一同登陆并一番寻找后，见过一名自称卡尔的老人，卡尔给出一栋门让镜像菲莉帕穿越过去，由于卡尔的出现十分诡异，麦可儿想阻止，但镜像菲莉帕决定誓死一搏。

卡尔公布了他真正的身份——永恒守卫者，一个在“时间战争”中多方争夺的力量，由于厌倦时间战争而试图躲藏起来，但由于球体数据认为能拯救镜像菲莉帕而给出了他的行踪。卡尔有感于镜像菲莉帕在这另一个镜像世界时空的良好表现，愿意给出一个适合镜像菲莉帕存活的时空，镜像菲莉帕就此与麦可儿分别。

Discovery ventures to the Verubin Nebula, where Burnham, Saru, and Culber make a shocking realization about the origin of the Burn. The rest of the crew faces an unexpected threat.

As the Emerald Chain tightens its grip and the mystery of the Burn is finally solved, Burnham and the crew have one last chance to save themselves - and the Federation.

在花了几个月的时间将联邦与遥远的世界重新联系起来之后，迈克尔-伯纳姆船长和发现号的船员被派去援助一个受损的空间站——一个看似例行的任务，却揭示了一个可怕的新威胁的存在。

萨鲁回来帮助发现者号揭开了一种异常具有破坏性新力量的神秘面纱。当伯纳姆领导船员时，她也必须找到一种方法来帮助萨鲁以应对难以想象的损失。

Burnham and Tilly hunt the killer of a Starfleet officer as Stamets and the science team race against the clock to prevent the anomaly from killing anyone else.

Tilly and Adira lead a team of Starfleet Academy cadets on a training mission that takes a dangerous turn. Meanwhile, Burnham is pulled into tense negotiations on Ni’Var.

Burnham and Book race to evacuate a group of stranded colonists in the anomaly’s path as one of the Federation’s brightest scientists comes aboard the U.S.S. Discovery to do high-stakes research with Saru and Stamets.

Seeking answers, the U.S.S. Discovery ventures into a subspace rift created by the Dark Matter Anomaly. Meanwhile, Book faces a strange visitor from his past.

Tensions rise as representatives from across the galaxy gather to confront the threat of the Dark Matter Anomaly. Zora's new sentience raises difficult questions.

Following a hunch, Captain Burnham tracks Book to an old haunt from their courier days and gets drawn into a high-stakes competition for a powerful weapon.

Captain Burnham and the U.S.S. Discovery race to stop Book and Ruon Tarka from launching a rogue plan that could inadvertently endanger the galaxy.

Captain Burnham and her crew must go where few have gone before: beyond the Galactic Barrier. Meanwhile, Book learns the truth of what drives Ruon Tarka.

While Captain Burnham leads an away mission to a planet that was once home to the aliens responsible for the DMA, Book and Tarka secretly infiltrate the U.S.S. Discovery.

As the DMA approaches Earth and Ni’Var, Captain Burnham and the crew of the U.S.S. Discovery attempt to make First Contact with the powerful species responsible before it’s too late.

The DMA approaches Earth and Ni’Var. With evacuations underway, Burnham and the team aboard the U.S.S. Discovery must find a way to communicate and connect with a species far different from their own before time runs out.

伯纳姆船长和美国海军发现号被派去取回一艘有 800 年历史的神秘罗慕兰船只；直到隐藏在里面的神器被盗，引发了一场史诗般的追逐。与此同时，萨鲁获得了终生难忘的职位，而蒂莉的努力却让她陷入了错综复杂的秘密之网。

在萨鲁作为伯纳姆船长的一号人物的最后一次任务中，团队冒险前往一个看似废弃的星球，寻找银河系中最伟大的宝藏。

格雷和萨鲁担任大使的第一天因他与特丽娜的订婚而变得复杂。

在寻找下一条线索的路上，美国发现号被一种神秘武器破坏，伯纳姆船长、雷纳和斯塔梅茨成为唯一有可能及时拯救这艘船的船员。

Captain Burnham and Book journey into extradimensional space in search of the next clue to the location of the Progenitors' power. Meanwhile, Rayner navigates his first mission in command of the U.S.S. Discovery, and Culber opens up to Tilly.

While undercover in a pre-warp society, Captain Burnham is forced to consider breaking the Prime Directive when a local tradition threatens Tilly's life. Meanwhile, Culber tries to connect with Stamets, and Adira steps up when Rayner assigns them a position on the bridge.

With Moll and L'ak finally in custody, the Federation is pulled into a diplomatic and ethical firestorm when the Breen arrive and demand they be handed over. Meanwhile, a frustrated Book looks for ways to help as Tilly, Adira, and Reno work to decipher the latest clue.

When Captain Burnham is trapped within a “mindscape” designed to test her worthiness to retrieve the Progenitor's powerful technology, Book, Rayner, and the crew of the U.S.S. Discovery must hold off the Breen long enough for her to escape.

After Moll and the Breen capture a mysterious structure that contains the Progenitors' power, Captain Burnham must lead a covert mission to retrieve it before the Breen figure out how to use it.

Trapped inside a mysterious alien portal that defies familiar rules of time, space, and gravity, Captain Burnham must fight Moll – and the environment itself – in order to locate the Progenitors' technology and secure it for the Federation. Meanwhile, Book puts himself in harm's way to help Burnham survive and Rayner leads the U.S.S. Discovery in an epic winner-takes-all battle against Breen forces.