Within the series' narrative, the Doctor is a centuries-old alien, a Time Lord from the planet Gallifrey, who travels in time and space in his TARDIS, frequently with companions. When the Doctor is critically injured, he can regenerate his body but in doing so gains a new physical appearance and with it, a distinct new personality. McGann portrays the eighth such incarnation, a passionate, enthusiastic, and eccentric character. His only companion in the television movie is Grace Holloway (Daphne Ashbrook), a medical doctor whose surgery is responsible for triggering his regeneration. In the continued adventures of the character depicted in audio dramas, novels and comic books he travels alongside numerous other companions, including self-styled "Edwardian Adventuress "Charley, the alien Destrii and present-day humans Lucie and Sam.
The Eighth Doctor debuts in the TV movie, Doctor Who. While transporting the remains of his longtime nemesis the Master to Gallifrey, the Seventh Doctor (Sylvester McCoy) is caught in the crossfire of a gang shoot-out in 1999 San Francisco's Chinatown, USA. He is taken to a hospital where surgeons, confused by his double heartbeat, attempt to correct a non-existent fibrillation. These efforts instead "kill" the Doctor, and he is taken to a morgue where after several hours—due to the effect of anaesthetic on his alien biology—he finally regenerates into his eighth incarnation (McGann). The Master manages to cheat death, and while the Doctor is on Earth his spirit takes over the body of a paramedic named Bruce (Eric Roberts). The Master (Roberts) then attempts to steal the Doctor's remaining lives by opening the Eye of Harmony inside the Doctor's time machine, the TARDIS, nearly destroying the Earth in the process. However, the Doctor and his companion Dr Grace Holloway (Daphne Ashbrook) are able to prevent the Earth's destruction, and the Master is sucked into the Eye.
The TV movie did not lead to the commissioning of a revived television series, and while Eighth Doctor stories continued in other media, Doctor Who did not air again on television until 2005. After this, footage and stills from the TV movie would be used in later episodes "The Next Doctor" (2008), "The Eleventh Hour", "The Lodger" (both 2010) and "Nightmare in Silver" (2013). Edited archive footage in "The Name of the Doctor" very briefly shows the Eighth Doctor sharing an adventure with the Second Doctor(Patrick Troughton).
McGann reprised the role for a webcast mini-episode "The Night of the Doctor" in 2013, which precedes the 50th anniversary special, "The Day of the Doctor". He is shown to be a conscientious objector to the raging Time War between Daleks and Time Lords, and is killed when attempting to save a young woman who rejects salvation at the hands of a Time Lord. He awakens in the company of the Sisterhood of Karn, who explain he has died and been temporarily resurrected. They urge him to bring the War to an end, and give him a choice of elixirs to trigger his regeneration. Saluting his various companions, he drinks an elixir designed to produce a warrior, regenerating into the War Doctor (John Hurt).
The Eighth Doctor encouraged those around him to seize life instead of withdrawing from it. He also seemed to enjoy giving people hints of their own futures, probably to prod them into making the right decisions. It is unclear if this Doctor's knowledge of people's futures comes from historical expertise, psychic power, or precognitive ability.
As with the Fifth and Eleventh Doctor, the debonair Eighth Doctor's youthful, wide-eyed enthusiasm actually hid a very old soul with perhaps a darker side. In fact, whereas the Eighth Doctor of the audio plays (voiced by McGann) and the comic strip hew closely to the television movie Doctor, the Eighth Doctor of the novels exhibited what was, at times, a much darker personality, perhaps due to the rather traumatic adventures he underwent (including being trapped in an inescapable prison for three years; the apparent destruction of his TARDIS; the discovery of a Future War that would all-but-dehumanise his people; and the temporary loss of his second heart). In the audio dramas the Doctor becomes a more traumatized figure towards the end of the New Eighth Doctor Adventures.
The Eighth Doctor also attracted controversy in the television movie, breaking the long-standing taboo against romantic involvement with his companions by kissing Grace Holloway. Fans were divided on this. In the spin-off media that followed, the Eighth Doctor has often been the object of romantic interest, but has shown little to no romantic inclinations of his own.
In all his iterations, the Eighth Doctor has proven extremely prone to bouts of amnesia, a tendency apparently inspired by the plot of his sole television appearance. He also demonstrates, in his first and only televised appearance, a penchant for sleight of hand. He manages to "lift" or pickpocket various items from certain people he meets during his first adventure.