To celebrate David Tennant, let’s remember some of his best Doctor Who moments.

Even though David Tennant has moved on from Who, we’ll always remember him as one of sci-fi’s greatest heroes. It’s been years since the Tenth Doctor saved Wilfred Mott from a radiation chamber and triggered his own regeneration. We’ve had another lovable Doctor come and go, and we’re now onto Twelve (technically Thirteen, we’ve since learned!) but we’re not ashamed to admit that we still miss David Tennant’s Ten and we probably always will.

A Completely New Man — ‘The Christmas Invasion’

The Doctor has only just regenerated into Ten and first on the agenda is dealing with Prime Minister Harriet Jones. This scene is not only incredibly well-acted, it’s also very important in distinguishing David Tennant as in his own Doctor identity. “Don’t challenge me, Harriet Jones because I am a completely new man. I could bring down your government with a single word.” It is the first time that Tennant gets to show us who his Doctor will be as the character begins to discover it for himself. Tennant so easily switches from feeling joyous at seeing Rose and the others to rage for what Harriet has done – this is a Doctor with a much shorter fuse than Nine.

Possessed by Cassandra — ‘New Earth’

Rose Tyler’s first TARDIS outing with the Tenth Doctor ends up with both of them getting used as a host body by Cassandra, a skin-creature ‘human’ that Rose and the Doctor have encountered before. Adjusting to change and getting to know someone new is tough at the best of times without a meddling being’s consciousness getting into the mix! This is one of David Tennant’s funniest scenes – after his dramatic introduction, he gets a chance to play around quite a bit in his first proper episode as the Doctor both with some brilliant physical comedy and some great campy dialogue. Cassandra’s interference also serves another purpose – it reveals that the Doctor and Rose find each other pretty damn foxy, and they even share a kiss that leaves them both a bit gobsmacked.

The Wall Between The Worlds — ‘Doomsday’

David Tennant’s first season of Doctor Who ends with the Doctor and Rose being separated in parallel worlds after saving the world together. Their eventual farewells are tear-jerking, but this scene – the moment and aftermath of the separation itself – is the stronger performance from Tennant. By the time they’re saying goodbye via hologram in Bad Wolf Bay, the Doctor has managed to put on a brave face and smile matter-of-factly while Rose sobs over him. That’s what this Doctor does – he represses and covers up whenever he can, it’s his defense mechanism. Here, his walls are, ironically down – he’s terrified and horrified at losing her, and as the opening between the universes is closed, he looks like the life has been sucked out of him. His eyes do all the work here.

Expelliarmus! — ‘The Shakespeare Code

To lighten the mood a bit, here’s a moment from one of the more light-hearted but still incredibly clever episodes. As the Doctor gets acquainted with Martha Jones, the pair travel back in time to meet William Shakespeare and naturally get caught up in a witchcraft-like alien attack at the Globe Theatre. Tennant flirts his way through the episode with sheer delight, and at crunch-time, he’s the one to inspire and motivate the greatest wordsmith in history. The Doctor and Shakespeare give new meaning to the “power of words,” but it’s Martha who has the clincher with a little bit of help from J.K. Rowling. This is good old fashioned Doctor Who fun.

The Death of John Smith — ‘The Family of Blood’

In the two part episode “Human Nature/Family of Blood,” the Doctor goes into hiding and we see David Tennant portray a normal human being in 1913 with an entire life’s worth of TARDIS-created memories. The Doctor has used the alias ‘John Smith’ pretty frequently, only this time he really is John Smith because he doesn’t know he’s pretending. It’s a tricky bit to portray the Doctor as Doctor and human all in one, but Tennant pulls it off, supported by Jessica Hynes as the woman John Smith falls in love with. When Smith discovers the truth about himself and must choose to become the Doctor again, effectively killing himself, it’s really a moment where you are rooting for both sides and don’t know which you’d rather.

Don’t Blink — ‘Blink’

This is probably one of the most famous monologues in recent Doctor Who history, and for a very good reason. Not only is “Blink” a fantastic episode in and of itself, but it brought us one of the scariest villains in Doctor Who as well: the weeping angels. Ten may not be featured heavily in this episode, but the appearances he does make certainly stand out. The “timey wimey ball of stuff” bit always gets a laugh, but it’s the end of the recording that really gives you goosebumps. Even over a grainy video on a tiny screen, David Tenant can capture your attention. Every time we hear his speech about the weeping angels, we find ourselves glued to our televisions, unblinking.

River’s Sacrifice — ‘Forest of the Dead’

“Silence in the Library/Forest of the Dead” is our first introduction to River Song and from the moment she appears onscreen we know that she is important to the Doctor even though he doesn’t. By the end of the episode we still don’t know who River is to the Doctor, but he does. We learn that he gave her his real name some time in the future and that it would have only been said at a very specific and intimate moment… spoilers! While the fans won’t see this unfold for several more seasons, the agony on the Doctor’s face in the moment she says good-bye lets us know that this is a major loss. David Tennant doesn’t say much during this scene, but all the emotion is clear on his face. It is the moment that makes us want to know all about River Song and what the future holds for the Doctor.

Goodbye to Donna — ‘Journey’s End’

This scene is equal parts beautiful and heartbreaking, and even though we’re here to celebrate David Tenant’s incredible run as the Tenth Doctor, we also have to give a shout-out to Catherine Tate as Donna Noble. Still, however hard it must have been for Donna, it was probably a thousand times worse for the Doctor. Donna got to forget, after all, while Ten was left with the bitter heartache at seeing Donna revert back to her old habits. She had come so far with him, and had been the most important person in the universe for a period of time, but in the end, the Doctor had to send her home, wipe her memory of him and their adventures, and reverse all of the progress she had made as his companion. But it was to save her life, and the Doctor knew that any amount of pain he felt was worth it if it meant she continued to live.

Playing God– ‘The Waters of Mars’

“The Waters of Mars” special is a dramatic departure from David Tennant’s three seasons – here he plays a Doctor unchecked, arrogant and ruthless, at the end of his tether with loss and losing. He fights back against it, and for once, someone fights back against him. It’s actually hard to cull it down to a specific moment of the episode, but the moment when he makes the decision to go back and mess with a fixed point in time and save people who were in a sense heroes or idols to him is just brilliance. At the same time, you’re admiring his courage and willingness to break the rules and equally saying “NO!!! What are you doing?” It’s a wonderful range of what Tennant can do. He goes from hero to someone you’re disappointed in. You’re with Adelaide on this one 100%.

Ten meets Eleven — ‘The Day of the Doctor’

When Doctor Who celebrated its 50th anniversary in 2013, the special episode “The Day of the Doctor” involved filmed performances of a total of five Doctors past and present, archive footage of the rest, and a game-changing plot revealing that there’s hope for Gallifrey and that maybe the Doctor isn’t the genocidal monster he thinks he is. However, the most superficially exciting aspect of the episode was getting to watch two massive fan favorite Doctors – David Tennant’s Ten and Matt Smith’s Eleven – star alongside each other. Their first meeting will go down in Who history forever, with the bonus factor of finally finding out what went down between the Tenth Doctor and Elizabeth I!

— Related: Ten more great David Tennant roles reviewed
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Karen Rought, Laura Byrne Cristiano, Jennifer Lamoureux and Natalie Fisher contributed to this feature.