Star Trek: Discovery is hurtling towards its conclusion this Sunday, following two more episodes bursting with plot and character development.

Captain Gabriel Lorca met his end in “What’s Past Is Prologue,” wrapping up Discovery’s visit to the Mirror Universe, and “The War Without, The War Within” did not let up as the crew returned to the Prime Universe nine months after it left, only to find a Federation suffering massive losses against the Klingons.

Let’s take a look at the references to previous Star Trek canon in these two episodes!

1. Mirror, Mirror

Early in “What’s Past Is Prologue,” Mirror Lorca catches Mirror Landry up with how he survived the destruction of the ISS Buran. While being pursued by the Charon, the Buran drifted into an ion storm as Mirror Lorca was beamed back to the ship, causing a transporter accident that beamed him into the Prime Universe.

This is the same way Kirk, Scott, McCoy, and Uhura accidentally traveled into the Mirror Universe in The Original Series episode “Mirror, Mirror.” Presumably, just like their Mirror counterparts crossed into the Prime Universe, Prime Lorca was transported to the Mirror Universe. His fate is currently unknown.

2. The No-Win Scenario

In “What’s Past Is Prologue,” while rousing the crew into action to attack the ISS Charon and destroy its mycelial reactor that has the ability to destroy the known Universe, Saru says that they will not accept a “no-win scenario.”

The no-win scenario refers to the Kobyashi Maru, the no-win test that Starfleet Academy cadets are forced to undertake in order to confront their own mortality. A later famous captain – James T. Kirk – was also not fond of the no-win scenario.

3. Warp Bubble

In order to both destroy the Charon’s mycelial reactor and travel back to their own Universe in “What’s Past Is Prologue,” the Discovery uses the warp bubble created around the ship when it engages its warp drive to protect the ship as it travels back to the Prime Universe.

Warp bubbles have been frequently referred to throughout Star Trek, including one time when Dr. Beverly Crusher became trapped in one in The Next Generation episode “Remember Me.”

4. Guest Quarters

After arriving aboard the USS Discovery in “The War Without, The War Within,” Emperor Georgiou is assigned to guest quarters, the traditional starship accommodations throughout Star Trek history for Admirals, diplomats, and now deposed imperial leaders from parallel dimensions.

Montgomery Scott famously found himself amazed when first seeing his guest quarters aboard the Enterprise-D, after being accustomed to the more spartan staterooms found aboard Constitution-class ships. (“Relics”)

5. Auxiliary Power

Due to its travel between universes, the Discovery is operating on auxiliary power at the beginning of “The War Without, The War Within.”

Auxiliary power is a common system across starships throughout the Star Trek canon designed to be used in emergency situations to supplement or replace main power when it goes offline.

6. Starfleet Intelligence

Ash Tyler reveals to Saru early in “The War Without, The War Within” that the Klingon House Mokai performed a “species reassignment” procedure on Voq, a procedure developed to infiltrate Starfleet Intelligence.

Starfleet Intelligence is the intelligence agency for the Federation and has been mentioned multiple times throughout Star Trek, including The Next Generation episode “The Pegasus,” and Deep Space Nine episode “Inquisition.”

7. Command Codes

When Admiral Cornwell, Sarek, and a security team beam aboard the Discovery in “The War Without, The War Within,” Cornwell takes command of the ship using her command code – Pi-Beta-6.

Many other command codes in Star Trek are also a combination of Greek letters and Arabic numbers – Janeway’s was Pi-1-1-0 in multiple episodes, and Picard’s in Star Trek: First Contact was 4-7-Alpha-Tango. Data also used an extremely lengthy command code to freeze his hold over the Enterprise-D in “Brothers.”

8. Casualties of War

In “The War Without, The War Within,” Cornwell is catching the crew of the Discovery up on the events of the last nine months. She describes how the USS Saratoga and Starbase 12 were destroyed in Klingon attacks.

Three other ships bearing the name Saratoga have been seen or referenced previously; in Star Trek IV: The Voyage Home and the Deep Space Nine pilot “Emissary” the Saratoga is a Miranda-class starship, and there was also a 22nd Century Saratoga in the United Earth Fleet.

Starbase 12 is mentioned in five episodes of The Original Series and The Next Generation.

9. Terraforming

In “The War Without, The War Within,” Stamets implants a moon in the Delta system with technology to allow it to quickly grow spores and replenish the Discovery’s supply. The process is referred to as terraforming, the means by which a planet is transformed and (as commonly understood) made habitable.

The most famous case of terraforming was conducted by the Genesis Device in Star Trek II: The Wrath of Khan. Perhaps some of the technology used in Stamets’s experiment was a precursor to Carol and David Marcus’s research that led to the Genesis Device.

“Home Soil,” part of TNG’s first season, was set on a planet during the early stages of human terraforming efforts.

10. Federation Council

In “The War Without, The War Within,” Sarek tells Admiral Cornwell that the Federation Council has approved Emperor Georgiou’s proposed plan for drastic measures to win the war against the Klingons.

The Federation Council has been referenced many times in Star Trek history, and seen most prominently in Star Trek IV: The Voyage Home.

11. It’s been a long road…

“No human has set foot on the Klingon homeworld since Captain Jonathan Archer and the crew of the Enterprise NX-01 a hundred years ago.” The plot of “Broken Bow” – this one sort of speaks for itself!

And the most blatant call out to previous Star Trek thus far in Discovery, I think. I, for one, am not complaining.

*   *   *

In discussing a plan to travel to the Klingon homeworld and take the fight to the enemy, the senior staff of Discovery review a holographic representation of Qo’Nos that has a number of geographical features referenced in previous Star Trek canon.

I couldn’t quite read them all, but here are the ones I could see:

First City (TNG: “Sins of the Father”)
Central Plains (TNG: “Hollow Pursuits”)
Lake of Lusor (TNG: “Rightful Heir”)
Kang’s Summit (DS9: “In Purgatory’s Shadow”)
Ketha Province (DS9: “Once More Unto the Breach”, “Star Trek Into Darkness”)
Caves of No’Mat (TNG: “Rightful Heir”)
Caves of Kahless (VGR: “Day of Honor”)
Skral River (DS9: “The Way of the Warrior”)
Mekro’vak Region (DS9: “Looking for par’Mach In All The Wrong Places”)

One episode left to go this season — we’ll see what familiar and fantastical Canon Connections Discovery brings us in “Will You Take My Hand?” this weekend!