Since its early beginnings in 1963, Doctor Who has seen some of the UK's best actors grace the lead role. Each Doctor, from William Hartnell to Jodie Whittaker, has presented their own take on the part and captivated audiences throughout their adventures in space and time.

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Arguably the greatest to play the legendary Time Lord is David Tennant, who featured in some of the 2005 revival's most memorable scenes. The Casanova star's charming and carefree take on the character proved an instant hit with audiences upon his debut in 2005's "The Parting Of The Ways," with many viewers still considering him the best Doctor to date.

His Humanity

The Tenth Doctor raising a device in Doctor Who

As an ancient alien from Gallifrey, the Doctor is not always confident at dealing with human interaction. David Tennant's Doctor bucks that trend, however, and presents viewers with an incarnation who better understands the art of human communication. This Doctor is the incarnation who forms the biggest personal attachment to those he meets on his travels.

The Tenth Doctor particularly takes great joy in the company of his companions, but equally struggles to process the emotional pain when they are forced to tragically part ways. This humanity helps to make Tennant's Doctor feel instantly relatable to audiences, whilst allowing David Tennant to give many moving performances throughout his tenure.

His Accent

The Tenth Doctor looking confused in Doctor Who

When David Tennant was cast as the Doctor in 2005, one of the biggest creative decisions regarding his incarnation involved what accent he would use. As previous Doctor Christopher Eccleston had retained his northern tones, then-current showrunner Russell T Davies opted against the idea of having two consecutive Doctors with strong regional dialect, and so asked David Tennant to drop his Scottish accent.

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In his depiction of the Doctor, David Tennant delivers a masterclass in how to effectively portray another accent. Tennant's new dialect is so convincing that it's easy to forget that he's originally from Scotland, as he provides a flawless interpretation of his incarnation's cockney rhythms and effortlessly disguises his broad Scottish voice.

His Chemistry With Billie Piper

The Tenth Doctor and Rose smiling for the camera in Doctor Who

One of the biggest highlights of the 2005 revival's first series was Billie Piper, who gave an endearing performance as companion Rose Tyler. Many fans were ecstatic when she decided to stay on for a second series, and the result was arguably one of the strongest Doctor and companion pairings yet.

David Tennant and Billie Piper demonstrate an astonishing amount of chemistry during their fourteen episodes together, leading to some Doctor Who viewers describing Ten and Rose as the perfect couple. The Doctor and Rose's gleeful delight in the face of danger and their blossoming romance make them one of the show's most captivating TARDIS teams, with the actors' strong friendship reflecting in the final piece.

His Love Of Languages

The Tenth Doctor stepping out of the Tardis in Doctor Who

The Doctor has traversed many different locations across the years, but this has rarely been reflected in the character's word usage. David Tennant's Doctor, however, developed a particular love for embracing different languages, from both Earth and also other planets. This incarnation frequently uses words from outside of the UK, demonstrating just how well-traveled the Time Lord has become.

The Tenth Doctor has embraced everything from the Tritovore's native language to 'Ancient North Martian', but perhaps the most memorable is his use of French and Italian words. David Tennant's Doctor frequently yells phrases such as "Allons-y" and "Molto Bene" throughout his run, and he carries it off with style, bringing a significant degree of fun and education to this incarnation's adventures.

Voyage Of The Damned

Kylie Minogue and David Tennant in a promo image for the Doctor Who Christmas special Voyage of the Damned

Considered by some fans to be one of Doctor Who's greatest Christmas Specials, "Voyage Of The Damned" aired in 2007 to one of the show's biggest audiences. Over thirteen million viewers tuned in to watch this festive televisual blockbuster, and it's not hard to see why. This Special feature not only seen a magnificent star turn from Kylie Minogue but it is also one of David Tennant's finest performances.

David Tennant shines throughout "Voyage Of The Damned," as he delivers a particularly grand speech. As the passengers on-board intergalactic cruise liner begin to question the Time Lord's authority, the Doctor informs the group exactly why he should be trusted. Tennant dominates the screen with his presence, as he delivers one of the show's most rousing moments.

His Fanboy Enthusiasm

David Tennant poses as the Tenth Doctor in a corridor.

A fan since the age of three, Doctor Who was a key inspiration behind David Tennant becoming an actor (according to What's On Stage), and his love for the show is reflected in his performance as the Doctor. Tennant reacts to the returning elements featured during his era with infectious glee, and this is most notable in the episode "School Reunion."

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"School Reunion" features the return of popular companions Sarah Jane Smith and K9, with original actors Elisabeth Sladen and John Leeson reprising their roles. David Tennant's delight at seeing these iconic characters translates perfectly to his depiction of the Doctor, suggesting the character is excited to meet his old friends again. Tennant is also able to draw upon his own fan knowledge of the Doctor's travels, as his acting in this episode effectively communicates the shared history between the Time Lord and his past friends.

His Dark Moments

The Tenth Doctor in a spacesuit in Doctor Who

The Tenth Doctor may be known largely for his cheery demeanor, but underneath it all, there's underlying darkness. David Tennant's incarnation has on occasion shown this inner fury and made life increasingly more difficult for those who dare to cross his path. Tennant plays these moments particularly well, showing exactly why he was cast in the lead role.

David Tennant's darkest performances as the Doctor come in "Human Nature/Family Of Blood" and "The Waters Of Mars." In "Human Nature/Family Of Blood," Tennant communicates his Doctor's inner anger perfectly without uttering a single word, as the Time Lord punishes the Family of Blood in some particularly cruel ways. "The Waters Of Mars," meanwhile, sees the Doctor declare himself the "Time Lord Victorious," and the conviction in David Tennant's delivery make this a particularly chilling scene to witness.

His Quirks

The Tenth Doctor looking surprised in Doctor Who

One of the key aspects the Doctor is known for is their eccentricities. Whilst the Tenth Doctor is not quite as eccentric as past incarnations, he still possesses plenty of his own quirks. David Tennant imbues his take on the role with so many subtle nuances, which he combines with the odd behavior already described in Russell T Davies' screenplays.

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The Tenth Doctor's most famous quirk is perhaps his tendency to repeat certain words for dramatic or comedic value, but he has also displayed a love for 'little shops,' and donned a pair of 3D glasses to search for "void stuff." David Tennant seamlessly integrates these strange moments in his performance, whilst adding his own foibles into the mix, such as scratching the back of his ear or raising his left eyebrow to express surprise.

His Rapport With Catherine Tate

The Tenth Doctor and Catherine dressed as a bride in Doctor Who

When Catherine Tate was announced as the new companion in 2008, many viewers were taken by surprise. The actor had previously made a guest appearance as Donna Noble in "The Runaway Bride," with some audiences assuming this would be a one-off appearance. Her appointment proved to be one of the biggest successes of this Doctor's era, with many Doctor Who fans considering the Tenth Doctor and Donna to be the perfect comedic duo.

David Tennant and Catherine Tate demonstrate excellent comedic timing throughout the revival's fourth series, with the pair delivering many funny moments. Whether they are miming through windows or fighting aliens with water pistols, this pair never fail to raise a smile, and prove themselves to be one of Doctor Who's greatest pairings.

The End Of Time

The Tenth Doctor Regenerates in Doctor Who

The 2008 National Television Awards saw David Tennant announce he would be giving up the role of the Doctor, leaving many viewers gobsmacked. His final story would arrive in the two-part adventure "The End Of Time," and would prove to be one of David Tennant's finest hours in the lead role.

The star gives one of his most emotionally gripping pieces of acting to date, as he struggles to move on from his current incarnation. The Doctor's thoughts echo that of the audience, who are also struggling to say goodbye to the character's tenth body. David Tennant's final words "I don't want to go" are the most impressive aspect here, however, as he delivers this line with such deep emotional resonance.

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