One of the most popular locations on any Federation starship (or space station), the Holodeck is one of Star Trek‘s many enduring science fiction legacies. However, while the Holodeck itself may be plenty impressive, the sentient holograms it can generate could be even more impressive still. Because of this, here are 6 sentient holograms from across the Star Trek universe.

Professor James Moriarty

Daniel Davis as Hologram Moriarty on Star Trek: The Next Generation.

Perhaps the most famous sentient hologram is based on Professor James Moriarty from the Sherlock Holmes stories by Arthur Conan Doyle. Hologram Moriarty (Daniel Davis) is first introduced in Star Trek: The Next Generation season 2’s “Elementary, Dear Data.” He is created by Geordi La Forge (LeVar Burton) at the request of Data (Brent Spiner), who requests a worthy adversary. Unfortunately, a perfectly timed energy surge completes the project a little too well. At the end of the episode, Jean-Luc Picard (Patrick Stewart) is able to compromise with Moriarty, who wants to be freed from the Holodeck.

RELATED: Star Trek: Picard Season 3: Everything to Know About Hologram Moriarty

Hologram Moriarty returns in TNG season 6’s “Ship in a Bottle.” Years later, Moriarty is still confined to the Holodeck. At the conclusion of the episode, Picard entraps Moriarty in a program called Picard Delta One. Because this simulation of the universe convinces Moriarty he has escaped from the confines of the Enterprise-D Holodeck, it placates the sentient hologram. What becomes of Moriarty after this episode is currently unclear. However,  it is worth noting that in Star Trek: Picard season 3’s “Imposters,” it is revealed that contemporary Starfleet technology includes a mobile hologram emitter, making Moriarty’s demand a possibility by the 25th Century.


Geordi (LeVar Burton) discovers the object in Repair Bay 5 in TNG's "Emergence."

Cargo Bay 5 is an active location on any Starfleet ship.

In TNG season 7’s “Emergence,” a new kind of sentient life expresses itself through the Holodeck. The crew becomes aware of this when Data’s performance of Tempest monologue is interrupted by the Orient Express. When the affected Holodeck is accessed, characters from many different programs appear as passengers on the train.

Eventually, Geordi discovers an inexplicable object in Cargo Bay 5. Thanks to the connection between the transporter and replicator systems, and an infusion of vertion particles furbished by Geordi’s resourcefulness, the consciousness that has inhabited  Enterprise-D‘s Holodeck is able to bring a new kind of life into being. As the being leaves the ship, the Holodeck deactivates. Were the characters sentient holograms or simply a means for the enigmatic entity to express itself?

Vic Fontaine

James Darren as Vic Fontaine on Star Trek: Deep Space Nine.

Holodecks played an important role on Star Trek: Deep Space Nine. Among other factors, this is thanks to the fact that Quark’s has many Holodeck suites for customers to enjoy. Doctor Julian Bashir (Alexander Siddig) and Miles O’Brien (Colm Meany) take full advantage of these facilities, often playing war games together. And in DS9 season 7’s “Take Me Out to the Holodeck,” the whole station crew gets involved in a memorable baseball game.

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However, the DS9 Holosuite antics also lead to the introduction of Vic Fontaine (James Darren) in season 6’s “His Way.” A sentient hologram who knows from the start what he is, this lounge singer casts a long shadow over the series, playing a key role in DS9 seasons 6 and 7. Later, in Star Trek: Lower Decks season 2’s “We’ll Always Have Tom Paris,” a billboard on Qualor II suggests Fontaine’s singing career takes off after the conclusion of DS9.

The Doctor

Robert Picardo as The Doctor.

Accept no emergency medical substitutes.

In the first episode of Star Trek: Voyager, “Caretaker,” the eponymous ship is transported deep within the Delta Quadrant. In the process, the ship’s doctor is killed. Fortunately, Voyager is equipped with an Emergency Medical Hologram (Robert Picardo). Soon the EMH is calling himself “The Doctor.” He goes on to play a major role in the series. Consequently, he serves to vastly expand viewer understanding of holograms within the Star Trek universe.

Thanks to an agreement with Captain Kathryn Janeway (Kate Mulgrew), The Doctor is able to determine when his program activates and deactivates. Once combined with a plethora of other autonomous personal exploration, this leads to the evolution of not just The Doctor himself, but of Federation hologram technology generally. Because of this fact, it is likely that the mobile emitter discussed in Moriarty’s entry above and the special hologram tech aboard the Star Trek: Prodigy’s USS Protostar are each the direct result of the hologram research conducted by Janeway and The Doctor on the way back to Earth from the Delta Quadrant.


"Terminal Provocations" -- Pictured Eugene Cordero as Ensign Rutherford, Jack MacBrayer as Badgey, and Noël Wells as Ensign Tendi of the CBS All Access series STAR TREK: LOWER DECKS.

Photo Cr: Best Possible Screen Grab CBS ©2020 CBS Interactive, Inc. All Rights Reserved.

Can he teach you a lesson? On Lower Decks, Badgey (Jack McBrayer) is the beta training hologram programmed by Ensign Samanthan Rutherford (Eugene Cordero). Unfortunately, Rutherford unknowingly included code that was crafted by his younger, angrier self. This causes Badgey to have homicidal daddy issues. In the first season, Badgey tried to kill Rutherford and D’Vana Tendi (Noël Wells). Later, Badgey succeeds in killing Shax (Fred Tatasciore). 

RELATED: Could Badgey return? Check out our 2023 Star Trek predictions

Unfortunately, it does not seem as though Badgey has been vanquished in any sense. Alongside other possibilities, a copy of his programming is preserved on Rutherford’s implant. After being left in the Kalla System after the events of the Lower Decks season 1 finale, “No Small Parts,” the implant was retrieved by an unknown actor at the conclusion of the season 3 finale, “The Stars at Night.” When will Badgey return to burn our heroes’ hearts in a fire?

Hologram Janeway

STAR TREK: PRODIGY: "Let Sleeping Borg Lie" Ep#112 -- Brett Gray as Dal and Kate Mulgrew as Janeway, in STAR TREK: PRODIGY streaming on Paramount+

Photo: Nickelodeon/Paramount+ ©2022 VIACOM INTERNATIONAL. All Rights Reserved.

However, a much more heroic sentient hologram appears in Star Trek: Prodigy season 1: Hologram Kathryn Janeway (Mulgrew). With an appearance and demeanor based on the character’s personality during the Star Trek: Voyager era, Hologram Janeway is an invaluable ally and mentor to Captain Dal R’El (Brett Gray) and his crew. Sadly, in the Prodigy season 1 finale, “Supernova: Part 2,” Hologram Janeway goes down with the Protostar. In the process, her sacrifice saves Starfleet from the malignant Living Construct.

But is that really the last we’ll see of Hologram Janeway? Now, the real Janeway has taken the former Protostar crew under her wing. Consequently, this ensures that Mulgrew will continue to have a role on the show either way. However, it is possible a time-travel duplicate version of the Protostar (or some other method of returning from the Black Mountain) could lead to Hologram Janeway’s return.

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STAR TREK: PICARD, Moriarty and The Seven-Per-Cent Solution

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