How Lucifer, Locke & Key, and The Sandman Are All Connected in the Comics

Netflix is home to two hit series based on popular fantasy comics -- Lucifer and Locke & Key -- and will soon be home to a third, The Sandman. What comic book fans may know that wouldn't be obvious to fans of the shows is that these three properties take place in a shared universe. At least, that's the case in the comics. Locke & Key co-creator Joe Hill have already stamped out any hope of a Netflix series crossover. But even with that in mind, some fans might want to know about these comic book connections. If you're wondering how the worlds of Sandman, Lucifer, and Locke & Key all coexist, then we can explain. 

Of course, SPOILERS for these longrunning comic book series -- and therefore possibly, their television adaptations -- follow. You've been warned.

(Photo: DC Comics)

Enter Sandman

It all started with The Sandman. Despite being the last of these three series to have its television series debut, The Sandman was the first of their source materials published. Neil Gaiman co-created The Sandman with Sam Kieth and Mike Dringenberg and wrote all 75 issues.

As Netflix viewers will soon discover, The Sandman follows Dream, one of the siblings in the conceptual family called the Endless. The series begins with Roderick Burgess, an occultist who had hoped to capture Death of the Endless, capturing her brother, Dream, instead. Eventually, Dream escapes imprisonment and must go on a quest to retrieve three powerful artifacts stripped from him when Burgess bound him.

(Photo: DC Comics)

Lucifer's Kingdom

That leads us to Lucifer. Gaiman, Kieth, and Dringerberg created the version of Lucifer that inspired the television show in The Sandman #4. In that issue, Dream ventures into Hell to retrieve one of the artifacts he'd lost, which had fallen into the hands of one of Hell's demons.

The issue establishes that Lucifer is one of the few beings in the universe more powerful than Dream, and the Morningstar isn't his biggest fan. Their relationship becomes tenser when Dream escapes from Hell with his artifact in hand, cowing Lucifer as he goes. Lucifer vows to destroy Dream when they next meet.

But Lucifer doesn't outright attack Dream. When Dream returns to Hell to free an old lover he had imprisoned there, Lucifer greets him peaceably and lets him go about his business. Lucifer then reveals that he has abdicated his position as ruler of Hell and "gifts" the Key to Hell to Dream to decide the realm's future. Lucifer departs for Earth, where Mike Carey and Peter Gross's spinoff Lucifer series begins, which is loosely the basis for the Lucifer television series.

(Photo: DC Comics/IDW Publishing)

Locke & Key: Hell & Gone

Years after The Sandman ended, in 2018, DC Comics revived the Sandman with a group of successor titles published under the Sandman Universe banner. The last of these (as of publishing) was a two-part crossover with Locke & Key subtitled Hell & Gone.

The story isn't about the Locke family seen in the original Locke & Key comics and Netflix series. Instead, it's the conclusion of a group of prequel comics collectively known as Locke & Key: The Golden Age. These stories chronicle the history of the Locke family and Keyhouse, focusing on Chamberlin Locke and his children.

By the time Hell & Gone takes place, Chamberlin Locke is an older man still mourning his son John's suicide, torturing himself by using the Echo Key to repeatedly summon a vision of the young man as he's tortured in Hell. Mary Locke -- Chamberlin's daughter and John's brother -- decides to take it upon herself to rescue John.

To gain the information she needs to go to Hell, Mary seeks the aid and knowledge of Roderick Burgess, who, at this time, has Dream in his basement. She trades Burgess one of the Locke family keys to see Dream. Dream gives Mary a hint that leads her to The Dreaming, Dream's kingdom, which is in disarray in his absence. In The Dreaming's vast library, she discovers a book that depicts the Key to Hell.

When she returns from The Dreaming, Mary heads back to Keyhosue and forges a replica of the Key to Hell. Armed with the Shadow Key and Angel Key, Mary uses the replica Key to Hell to gain entry to Lucifer's domain, this still being the era of the Morningstar's reign. Though pursued by Lucifer, Mary manages to escape Hell with her brother's soul. She then uses the Moon Key to deliver him to a happier afterlife.

Once there, Mary travels to the Silver City, where angels dwell. Through the paradoxical magic of a time loop, she's transported back in time to the moment of Lucifer's fall, and Mary's replica becomes the authentic Key to Hell, foisted upon the Morningstar in exile.

It's All Connected

That's how The Sandman, Lucifer, and Locke & Key are all connected. If you're interested in reading the entire saga for yourself, you can start with whichever is most of interest to you. Still, we'd recommend going for The Sandman first, at least through Season of Mists, and then Locke & Key: The Golden Age. (Lucifer is also excellent but not relevant to this particular story arc.)

What do you think? Let us know in the comments. All six seasons of Lucifer are streaming now on Netflix. The second season of Locke & Key recently debuted on Netflix. The Sandman will premiere on Netflix in 2022.