He appears alongside Peter Capaldi's Twelfth Doctor and his storylines stem primarily from being the colleague, and later boyfriend, of companion Clara Oswald, portrayed by Jenna Coleman.

He is a new Maths teacher at Coal Hill Secondary School in London, and is reasonably new to the profession having spent a number of years in the past serving with the British Army.

A dark past is hinted at when he avoids answering a question from one of his students on whether he has ever killed someone who wasn't a soldier, with a tear rolling down his cheek.

At the same time, the Doctor (Peter Capaldi) is attempting to explore the possibility that everyone has a constant companion, like a shadow, that is always with them, relating back to the recurring dream of the monster under the bed.

Clara is then stunned when the Doctor takes her to meet Orson Pink, a time traveller from 100 years in the future who has become stranded at the end of the universe.

Danny makes brief appearances in subsequent episodes in the series, and he supports Clara when she decides to stop travelling with the Doctor after he puts her in a vulnerable position in "Kill the Moon".

Her deception is exposed in "In the Forest of the Night", when Clara, Danny and a group of special needs students become stranded in an overgrown central London and are forced to call on the Doctor for help.

While inside the TARDIS, Danny discovers a pile of recent student papers Clara has been marking, proving she is in regular contact with the Doctor.

She is devastated when he dies of his injuries, but Danny's consciousness is brought to the Nethersphere, an artificial afterlife created by Missy (Michelle Gomez), a female version of the long-standing Doctor Who villain the Master.

Upset over this and Clara's reaction to his death, Danny is encouraged to delete his emotions, but does not do so before seeing Missy force the consciousnesses trapped in the afterlife back to their bodies, which have been "upgraded" to become Cybermen.

Following 2013's 50th anniversary celebrations, head writer Steven Moffat decided that he would bring in another teacher to work alongside Clara in exploring the school's roots.

[2] Coleman and Anderson had previously closely worked together on the ITV soap opera Emmerdale, where they played Jasmine Thomas and Ross Kirk respectively.

As part of the Mistress' plans, Danny was reincarnated as a Cyberman along with the other dead on Earth, but saved the day by taking control of the other Cybermen and leading them into the sky to explode and burn away clouds of Cyber spores meant to convert the living as well.

[9] Following his death, some fans campaigned to "keep Danny dead" in light of Steven Moffat's trend of resurrecting fallen companions including Clara and Rory Williams.