The character is introduced as the ordinary, working class boyfriend of Rose Tyler (Billie Piper), a London shopgirl who becomes a travelling companion to the Ninth and Tenth incarnations of an alien Time Lord known as the Doctor.

Mickey, terrified by the revelation that alien life exists, fails to impress the Doctor, who only invites Rose to be his travelling companion in time and space.

[2][3] A much younger Mickey, played by Casey Dyer, appears briefly when Rose attempts to alter her childhood in "Father's Day".

[4] In "Boom Town", Mickey later meets up with the Doctor, Rose and new companion Captain Jack (John Barrowman) in Cardiff, where he helps them foil a Slitheen plot.

There, Mickey is mistaken for his parallel universe doppelgänger "Ricky Smith", the leader of a human resistance group called the Preachers.

[8] However, Mickey makes a surprise reappearance in finale episodes "Army of Ghosts" and "Doomsday", wherein like the Cybermen, he and fellow Preacher Jake Simmonds (Andrew Hayden-Smith) are able to cross the Void into our world.

Both featured videos of Clarke as Mickey, informing the viewer of facts about the series, or introducing "missions" which would be played out in online Macromedia/Adobe Flash games.

For the "School Reunion" TARDISODE, Mickey is researching UFO sightings online when he is blocked by a notice referring to Torchwood, prompting him to call Rose to investigate.

In accepting the role Noel Clarke comments that he "had to have a lot of faith" in executive producers Russell T Davies and Julie Gardner because he felt the series was not of high quality at the time of its previous cancellation.

[19] Mickey was created alongside Rose's mother Jackie in order to explore the question of who is left behind after a companion leaves earth to travel with the Doctor.

[22] Clarke feels the character of Mickey wasn't widely liked in the first series, admitting that he also saw the part as a "kids’ TV" role.

Davies reveals that Clarke was excited about Mickey's development in the second series, particularly having the chance to carry a large gun and be an action hero.

[24] However, he felt that it provided a positive effect in that young fans of ethnic origin would no longer have to be a monster or alien when role-playing characters from the series.

[24] "Rise of the Cybermen" and its online Tardisode prequel, set in a parallel universe, featured Mickey's doppelgänger, Ricky Smith.

[27] The scene, included in the Series Two DVD release, shows Jake telling Mickey that he can't replace Ricky, as he will "never have another boyfriend like him.

"[28] Following Mickey's appearance in "Journey's End" the production team had intended for Clarke to join spin-off show Torchwood for its third series in 2009, but his career led him elsewhere.

[30] In their review of the episodes "Aliens of London" and "World War Three" Graeme Burk and Robert Smith praised the character's development stating that "by the time he faces down a Slitheen in his apartment, armed only with a baseball bat... you want him to become a regular companion."

[33] In a review for the follow-up, "The Age of Steel", Haque believed the episode was "worth watching" to see Mickey "finally [step] up and finds a purpose" and become a hero.