Lost in Space season 3 review: Netflix sci-fi's final outing is the show at its best

Having the 97 children parted from the adults for a full year means these kids have matured a lot in that time, and it’s been Judy who’s been keeping them together. With the adults elsewhere and much of the first few episodes here focusing on the teens, much of season three has more of a YA vibe than ever before. And be warned because this is a full spoiler review.

It takes a few episodes for the Robinsons to be reunited, and by mid-season, season three Lost in Space feels much like season one Lost in Space. It’s here that the gang speculate why the robots have recently scanned, but not killed Don (“like they were trying to guess my price at a supermarket,” he quips).

It turns out that the human body is, at an atomic level, regularly impacted by its environment (“some scientists think this makes our bodies like a point on the map of the universe,” points out Maureen) and that by following these cosmic breadcrumbs anyone with the right technology can travel to wherever that person has visited. And Don has been to Alpha Centauri.

Desperate to stop the Robots from setting off to the humans’ new home, Will confronts SAR and is stabbed through the heart. With the teenager close to death, the Jupiter sets off to alert the colonists of the imminent attack. While there, Will is given an artificial heart, while John and Maureen are told, to their horror, that the planet has no defence system. Later, it turns out there **is** one, and it’s Hastings (a wonderfully oily Douglas Hodge) who knows how to access it. The downside is that it can only be activated with a list of random words spoken out loud by just one man – the deceased Ben Adler.

Compiling an audio file of the command words, extracted from various voicemails and videos of Adler before he died, the colonists manage to trigger the planet’s defence system, but the Robots still manage to get through. It’s Will who works out what they’re after – it’s the alien engine from SAR’s ship, which the robots plan to use as a bomb.

With Will’s health failing, Robot repairs his artificial heart, seemingly destroying himself in the process. But when Will confronts SAR, the robot attempts once again to kill him, stabbing him in the chest. “He knew you’d go for my heart again,” Will says, and with that, Robot’s data is transferred, killing SAR and reviving Robot in the process.

An epilogue tells us that the robots that escaped their programming left Alpha Centauri, not telling the humans where they were going. “Now they’re writing their own commands, they’re all different,” Penny writes in her book. “Just like we are.”

And so that’s it. Three seasons and 28 episodes of Lost in Space finally wrapped up. While never being one of Netflix’s premiere-league series, it was a solidly unpretentious and broad-appeal sci-fi show and this final season has shown it at its best. There’s some truly jaw-slackening special effects work here, particularly in the closing showdown between the humans and the robots – CGI work that wouldn’t shame the final reel of an MCU movie.

Sure, the dialogue has often been cheesier than a Dairylea triangle and Robot generally had more depth than many of the show’s flesh and blood characters (hello John Robinson), but it’s been a fun ride these past three and a half years, and showrunner Zack Estrin always managed to make each season distinct.

Though the ending doesn’t specifically point to a sequel or spinoff (aside from Penny’s adding of ‘Of Chapter One’ after writing ‘The End’ in her book), it’d be good to catch up with the Robinsons a few years, or even decades, down the line. Its warm, feel-good heart is something that’s missing in much small screen sci-fi – and in that way, Lost in Space will be sorely missed.

Lost in Space season three is now streaming on Netflix. For more, check out our dedicated Sci-Fi page or our full TV Guide.