7 Best Peter Capaldi 'Doctor Who' Episodes to Rewatch for Season 10

Peter Capaldi’s 12th Doctor tends to alienate some Doctor Who fans, but the oldest and most acerbic incarnation of the Time Lord in recent history is the Time Lord at his most honest. He’s been darker, more brooding, and angrier than the fun-loving 11th and outright giddy 10th. Whereas those two both ran so desperately from their past, the 12th has consistently done the opposite, reconciling a dark personal history to redefine his future. And along the way, this version of the Doctor has adventures that are some of the show’s best episodes yet.

Capaldi’s Doctor has been around for over 2,000 years and his world-weariness shows, pushing Doctor Who closer to its roots: a grumpy old alien journeys through all of time and space in an attempt to cure his loneliness. As fans get ready for his final season as the Doctor, here are the seven best episodes that define the Peter Capaldi era of the 12th Doctor.

7. “Sleep No More”

Simply put, “Sleep No More” is one of the most fucked up episodes of Doctor Who ever and employs a found footage framework to great success. It opens on the lead researcher at Le Verrier Space Station explaining the dangers of the footage included in the message. The monster in this episode is a carnivorous form of life created in the 38th century by human sleep dust produced when sleeping in a pod designed to give a full night’s sleep in five minutes. The sand monsters consumed an entire ship of researchers, and the Doctor and Clara work with a four-man rescue team to unravel the mystery.

6. “Flatline”

“Flatline” famously debuted the tiny TARDIS after something leeches its “external dimensions,” but what begins as a fun, strange romp quickly turns dark as creatures that only exist in two dimensions and devour people as a means of testing out how to relate to three-dimensional space. The Doctor dubs them “Boneless,” and by the end of the episode the creatures are able to create shambling, monstrous shimmers that absorb and destroy everything in their path. It’s one thing to die, but to be ripped out of your dimensional constraints? That’s a whole new level of sci-fi horror.

5. “Into the Dalek”

In the 12th Doctor’s first adventure after his initial post-regeneration, we see a slightly confused new Doctor that struggles relating to even Clara. He’s also constantly questioning himself, which is a far cry from the bold bravado of his 10th incarnation and the indomitable silliness of his 11th. “Am I a good man?” is the pivotal question at the start of this adventure, which leads the Doctor and Clara literally inside a Dalek, leading both viewer and the Doctor himself to wonder if even his greatest enemies might be redeemable? Having the Doctor literally inside his greatest enemy makes for a great metaphor and results in one of the better Dalek episodes in the entire series.

4. “The Magician’s Apprentice”

The premiere of Peter Capaldi’s second season is a pivotal one for a number of reasons. We learn that the Doctor essentially created his worst enemy, the Daleks, by saving a young Davros, the boy that would one day invent the monsters. The Doctor handles the guilt and grief by … pounding on a guitar while riding a tank and wearing sonic sunglasses in 1138 Essex? It’s a bizarre, anachronistic moment that will forever define Capaldi’s Doctor, one that returns to a behavior typical of recent Doctors: running away, whether it’s from guilt or a fight or his own demise. The episode offers up the bonus of a Missy-Clara team-up.

3. “Listen”

The opening monologue of “Listen,” featured above, offers up just the right amount of foreboding for one of Capaldi’s absolute best early episodes, which tries to answer two frightening questions: What does the Doctor do when he’s alone, and what sort of creatures linger in his nightmares? Clara has a disastrously uncomfortable date with Danny that leads her to engage the TARDIS’s telepathic circuit to Danny’s childhood where they confront “a thing that must never be seen,” a creature theoretically perfect at hiding. Clara goes on to lead the TARDIS to the Doctor’s own childhood, where she is the monster under the bed, and it’s his story of fear that echoes throughout all of history. What starts out as mystery monster horror transforms into a meditation on the nature of fear itself and its capacity to inspire compassion over cowardice.

2. “The Zygon Inversion”

If the 12th Doctor gets fired up about anything that’s not saving or protecting Clara, it’s getting pissed off about the petty bullshit of lesser creatures. That’s ultimately what that Zygon-focused (UGH, Zygons AGAIN!?) two-parter in Season 9 is about. Impending global calamity is the name of the game, and Clara’s life is more threatened than ever as she’s captured and impersonated by a Zygon. “When I close my eyes,” the Doctor trembles, “I hear more screams than anyone could ever be able to count.” We realize in this moment, perhaps more than at any other moment — at least in 12’s tenure — just how much pain he is carrying.

1. “Heaven Sent”

Never before has Doctor Who been so utterly stripped down and simplified as when the 12th Doctor was trapped inside his own Confession Dial, a tool meant to trick the Doctor into revealing his knowledge of the Hybrid Prophecy that would supposedly destroy Gallifrey. What we ultimately get is the Doctor trapped in an isolated castle with no company save for a slowly moving wraithlike creature aiming to kill him. Shifting rooms and gears abound during his struggle for self-preservation. The plot weaves an exhausting loop as the Doctor eventually finds the way out: He must punch through a wall of Azbantium, a mineral 400 times harder than diamond. But it takes more four billion years to do this by teleporting his past self there thousands and millions of times to relive the same loop. The Doctor was never so grim and resolute as he is facing death countless times. He’s stubborn, relentlessly, and never so courageous.

The new season of Doctor Who, Peter Capaldi’s very last, kicks off April 15, 2017 on BBC and BBC America at 8 p.m. Eastern.