The crew of Discovery is sent to retrieve a mysterious artifact from an 800-year-old Romulan vessel, but find that they are not the only ones on the hunt. Meanwhile Saru considers his future.
With help from Book, Captain Burnham and the crew search the remnants of an extinct civilization for the next clue to a mystery that could reveal the secrets of creation itself. Book makes contact with the competition, and learns a starting secret about Moll and L'ak.
The hunt takes Discovery to Trill where Burnham, Culber, and Book face a dangerous test to obtain the next clue. Meanwhile Adira reconnects with Gray, and Saru learns that his relationship with T'Rina might hurt her politically.
After Burnham and Rayner begin jumping through time seemingly at random, they realize that Discovery has been attacked with a temporal weapon – and must find a way back in order to avert a catastrophic future.
The hunt for Moll and L'ak leads Discovery to a pocket dimension, where Captain Burnham and Book board a familiar ship from the Mirror Universe -- hoping not only to find the next clue but to bring in the pair of star-crossed lovers.
Michael and Tilly go undercover in a pre-warp society, where they join a spiritual pilgrimage to a high mountain tower in order to find the next clue – and save a civilization from extinction. Meanwhile Culber tries to make sense of how hosting Jinaal has changed him.
With Moll and L’ak finally in custody the Breen send a warship to demand they be handed over, putting Discovery and the Federation in the middle of a blood feud.
As Moll puts everything on the line by promising to deliver the Progenitors' tech to the Breen, Discovery enters the Badlands in pursuit of the final clue hidden inside a massive alien library.
After the Breen beat Discovery to their prize the crew hatch a risk plan to infiltrate the enemy dreadnought and steal it back. Meanwhile, Saru offers to represent the Federation in dangerous negotiations with the Breen.
As Discovery tries to catch the vault before it falls into a gravity well, Saru and Nhan risk their lives to intervene with the Breen – while Michael squares off with Moll inside the extradimensional world that hides the secrets of the Progenitors.
