Star Trek The Next Generation: Time’s Arrow, Explained

Key Takeaways

• In a Star Trek Lower Decks episode, the alternate universe Data’s severed head is discovered on a pre-warp planet.
• The encounter mirrors a TNG episode where the Enterprise-D crew found Data’s head in the 19th century, sparking a time-travel adventure.
• To repair the timeline, Data’s head is reattached in the future while Picard is saved from the past, with Guinan playing a mysterious role.

In a recent episode of Star Trek: Lower Decks, Lieutenants Junior Grade D’Vana Tendi, Beckett Mariner, and T’Lyn beamed down to Detmer III, a pre-warp planet, to prevent a potential violation of the Prime Directive. On the planet, they found the severed head of none other than Lieutenant Commander Data of the Enterprise-D. However, it’s an alternate universe Data, who comes from a universe where everything is purple.

Of course, avid Star Trek fans recognized this as a reference to the other time a Starfleet crew found Data’s severed head. In the Season 5 two-part episode “Time’s Arrow,” the crew of the Enterprise-D was called back to San Francisco to investigate an odd discovery: Lieutenant Commander Data’s severed head among artifacts from the 19th century.

Data’s Head and Its Implications

After researchers showed Data and Captain Jean-Luc Picard Data’s head, which had apparently been in a cave in San Francisco for over 500 years, they took the head back to the Enterprise-D for further examination. As Data examined his own severed head, the rest of the crew was visibly upset by the implications of finding it: that Data was going to die…in the past. The only two who weren’t upset were Data himself, who found knowledge of his death comforting because the ability to die made him more human, and Guinan, who made the mysterious comment, “Full circle,” without any further explanation.

Resuming their mission, the Enterprise-D entered the orbit of Devidia II, where scans detected high levels of triolic waves. Incidentally, Data’s tricorder had detected the same thing in the cave where his severed head was found. An away team beamed down to where the high level of triolic waves were located on the surface, which happened to be a cave similar to the one in San Francisco.

Inside the cave, the away team discovered all sorts of wacky time distortions. Lifeforms were present in the cave, but the crew couldn’t see them because they were out of phase with the away team’s timeline. When Data adjusted the phase variance, he observed lifeforms feeding on energy particles. Two Devidians, natives of the planet, approached Data and opened a temporal distortion, which enveloped Data. To his away team, Data was simply gone. Yet, Data found himself in 19th century San Francisco.

TNG in the 19th Century

As Data wandered around 19th century San Fran, the senior officers gathered on the Enterprise-D, trying to figure out what happened to Data. Lieutenant Geordi LaForge suggested that he could try to recreate what Data was doing before he disappeared. Since that was their only plan, Picard told him to take a team and get started. Then, Picard headed to Ten Forward to seek advice from Guinan. In her characteristically mysterious way, Guinan told Picard that if they didn’t find Data, he’d never meet her. Baffled, Picard beamed down to the surface to join the away team.

Meanwhile, in the past, Data struggled to build a device that could take him back to his time. While working on this, he discovered a picture of Guinan, in period-appropriate garb, in a newspaper. So he sought her out. They met at a literary reception for Samuel Clemens, better known as Mark Twain. Guinan didn’t recognize Data, given that they wouldn’t meet until centuries later, but Data explained the situation as well as how he knew her in the future. Guinan is confused, but as an alien with a lifespan of hundreds of years, she wasn’t too shocked by Data’s revelation.

In the cave on Devidia II, the away team figured out how to adjust the time variance, as Data had. They saw the same creatures he did, along with the Devidians. The aliens created another time distortion, and suddenly, the away team was also back in 19th century San Francisco.

As the away team got their bearings in their new surroundings, posing as a Shakespearean theater troupe, Data enlisted Guinan to help him get back to his own time. When they went to the hotel where Data had been building his device, they discovered a key component was missing. Moments later, they discovered Clemens hiding in the closet, the component in his hands. He’d suspected Guinan of being extraterrestrial for a while, and he believed his discovery of futuristic technology proved his theory. Clemens swore to expose them, and Guinan kicked him out.

The away team figured out that the Devidians were using a snake-like creature called an ophidian to create the space-time distortions, and concluded they must have a device that concentrated the creatures’ energy to control the distortions. As they tried to figure out the technology, they found Data, and 19th-century Guinan. They all make their way to the cave where Data’s head was found, in the future, and tried to create a time distortion using a snake-shaped cane, which was actually an ophidian.

But when the time distortion opened, the Devidians appeared and stole the cane. During the struggle with the Devidians, Picard was knocked out, and Data lost his head — literally. However, he did retrieve the cane. As the time distortion closed, Geordi grabbed Data’s body, and the away team jumped into the distortion. However, they couldn’t get to Picard in time. He was left behind in the 19th century, with Guinan.

Repairing the Timeline, and Data’s Head

Back on the Enterprise-D, the away team was accompanied by an unexpected tagalong: Clemens. Counselor Deanna Troi was assigned to babysit him and orient him to the 24th century.

Geordi took Data to Engineering, and attached the 19th-century head they’d found in San Francisco to his headless body. So, Data’s original head remained in the 19th century, but he got it back 500 years later. However, he couldn’t get Data to reboot.

Commander Riker sought out Guinan and demanded to know how he could get the captain back. She obviously knew how everything played out at the time because she was there, but she refused to tell Riker. She insisted that doing so would alter the past, so he’d have to figure it out himself.

Though the senior staff wanted to get Picard back from the past, they all agreed they couldn’t allow the temporal distortions to continue. They decided to blow up the cave so the Devidians couldn’t use its unique properties to open any more time distortions. Right on cue, Geordi figured out how to revive Data, and Data informed the senior staff that Picard had left a message in his memory banks warning him not to blow up the cave.

With the ophidian cane in their possession, the senior staff decided they should go back to get Picard. However, Clemens insisted he should be the one to do it, since he was in the wrong time period anyway. An away team accompanied Clemens to the cave, where he opened a temporal distortion and traveled back to the 19th century cave.

He found Picard and Guinan still in the cave, and instructed Picard on how to get back to his time. Hastily, Picard set everything up, and traveled home. Chief O’Brien beamed him out of the cave, and immediately afterwards, Commander Riker gave the order to blow up the cave.

Picard’s first stop, after thanking his crew, was Ten Forward, where he greeted Guinan with a big smile. For the first time, the two of them could reminisce on their actual first encounter, not the one Picard previously remembered.

Sources: Star Trek: The Next Generation episode “Time’s Arrow,” Star Trek: Lower Decks episode “Fully Dilated”