There have been some terrific Doctor Who Christmas specials since the series returned in 2005, but The Husbands of River Song made this list because it brought closure to a long-running storyline that began in season 4 when Alex Kingston made her first guest appearance as River Song. Through most of her time on the show, River knew more about the Doctor’s future than he did. Peter Capaldi’s Twelfth Doctor flipped the switch on River, in part because she had never met his incarnation of the Doctor before.

This time, the Doctor got to play the role of the companion to River, who missed some obvious clues about his true identity. The Doctor was clearly having a blast, even though he didn’t always approve of River’s tactics. When River recognized the man she loves, the Doctor finally showed River how much he loves her as well.

The first season of the revival series didn’t bring back anyone from the original version of Doctor Who. Season 2 quickly rectified that with a guest appearance by Elisabeth Sladen as Sarah Jane Smith, the Doctor’s companion during some of the peak years of the series in the ’70s. Sarah Jane’s return was beautifully handled, as her hard feelings about being abandoned by the Doctor gave way to the joy of seeing him again. The Doctor was also clearly proud of the woman that Sarah Jane had became.

Sarah Jane’s return was more than just an emotional link to the past. It allowed Sladen to finally get a spinoff series, The Sarah Jane Adventures, which was something that almost happened decades earlier.

The Doctor is many things, but rarely as angry he was in A Good Man Goes To War. Madame Vastra (Neve McIntosh) and her forces kidnapped the Doctor’s companion, Amy Pond (Karen Gillan), and forced her to give birth in captivity. The Doctor and Amy’s husband, Rory Williams (Arthur Darvill), responded by putting together a small army from across time and space to storm the Demon’s Run space station in order to save Amy and her newborn daughter.

This episode was also one of the rare occasions where the villains got the last laugh, and the Doctor’s triumph became a bitter defeat. Regardless, the final moments of the story were a revelation that there might be a happy ending at the end of this difficult time.

The Stolen Earth and Journey’s End pulled off a massive Doctor Who crossover story a decade before Avengers: Infinity War did the same thing for the MCU on the big screen. Every single companion from the revival series to that date returned for this two-part season 4 finale, which also featured guest appearances by the casts of the two spinoff series: The Sarah Jane Adventures and Torchwood.

Watching the Doctor’s friends rally around him was exciting and rewarding. Yet the episode’s emotional stakes came to rest on the Doctor’s bond with Donna Noble (Catherine Tate), who was perhaps his best friend among the companions. Donna saved the universe, and all it cost her was the chance to live a life of adventure with the Doctor and all the memories that went with that. It’s a good thing that the 60th anniversary specials gave the Doctor and Donna some much-needed resolution and a joyous reunion. We had to wait a long time to see that.

The second half of Doctor Who season 7 revolved around the mystery of the Doctor’s new companion, Clara Oswald (Jenna Coleman), who somehow simultaneously existed in multiple time periods. The Name of the Doctor peeled away the secrets of Clara’s purpose just as the Doctor discovered his final resting place in the future. There were also several callbacks to previous versions of the Doctor, both within the revival and the original series.

Despite the title of the episode, the Doctor’s biggest secret isn’t his name. It’s the chapter of his past that he kept hidden from everyone, which played out in The Day of the Doctor six months after this season finale aired.

Many Doctor Who fans point to Blink as the greatest episode of the series despite the fact that the Doctor barely appears in it. It also has a much scarier tone than most of the show’s episodes. This is a great standalone story featuring guest star Carey Mulligan before she went on to become an Oscar-nominated actress. Mulligan plays Sally Sparrow, a young woman who has never met or heard of the Doctor before.

Much to Sally’s surprise, she comes to realize that the Doctor is attempting to contact her from the past because he needs her help to send his TARDIS back in time to retrieve him. Standing in Sally’s way are the Weeping Angels, an alien race who look like statues whenever anyone lays eyes on them. But the second that their victims look away, the Angels move with startling speed. There’s only one solution: “don’t blink.”

The Doctor Who revival upped the stakes with its two-part season 2 finale, Army of Ghosts and Doomsday. The Doctor’s two greatest enemies, the Daleks and the Cybermen, came face-to-face before immediately declaring war against each other. Since both forces were invading Earth at the same time, that could have meant the end of humanity.

Thankfully, the Doctor and his companion, Rose Tyler (Billie Piper), come up with a solution… with an unintended consequence that forces them to say goodbye forever. This was Piper’s final episode as a regular cast member of the series, and at the time, it really did seem like the Doctor and Rose were parting for good just when they were about to acknowledge that they loved each other. The heartbreak in their farewell is unmatched.

The fifth-season premiere, The Eleventh Hour, may be the most perfect pilot episode that isn’t actually a pilot. Matt Smith’s first full episode as the Eleventh Doctor completely reset the board for the show, even as the Doctor was still wearing the rags of his previous incarnation.

After crashing to Earth in the past, the Doctor meets and befriends a young girl named Amelia Pond (Caitlin Blackwood). One slight time travel mishap later, the present day Amelia now goes by Amy, and she is understandably upset because she thinks the Doctor abandoned her. But they have much bigger fish fingers and custard to fry because the Doctor has to save the world without his TARDIS or his sonic screwdriver. And he’s got less than an hour to pull it off. Keep an eye out for Oscar-winner Olivia Colman as she makes a cameo late in the episode.

Peter Capaldi is one of the best actors to ever play the Doctor, and several of his episodes fell just outside of our top 10. However, Heaven Sent is in a league of its own, and it was all on Capaldi’s shoulders. For almost the entire episode, Capaldi is the only actor on screen as the Doctor finds himself a prisoner in a strange castle where he is stalked by a ghoulish creature known as the Veil.

This story took place immediately after the Doctor witnessed the death of one of his closest friends and companions. That left Capaldi with a lot of emotions to convey, including anger and grief, as the Doctor tried to come up with a way to escape. With no one else around to speak with, Capaldi essentially plays off of himself, and he gives an incredibly compelling performance. The ending is also up there with the all-time shocking cliffhangers in the history of the series.

Anniversary specials are often where the Doctors of the past meet the Doctors of the present. In the modern era, David Tennant and Matt Smith were the two most popular incarnations of the Doctor when they teamed up for the 50th anniversary special, The Day of the Doctor. Fans had impossibly high expectations for this special, and the episode surpassed them.

Since the Ninth Doctor actor, Christopher Eccleston, declined to return, showrunner Steven Moffat cast film veteran John Hurt as the War Doctor, a previously unknown incarnation of the Doctor who was physically older and more mature than his much younger versions from his personal future.

Tennant and Smith were hilarious together, but pairing them with Hurt raised the dramatic stakes and allowed all three of the Doctors to come to terms with their collective past. This happened during a fast-paced story that was nearly the length of a movie, which also set the stage for the next decade of Doctor Who adventures in an emotionally satisfying and exciting way.