Mir joined the Daily Jang (Lahore) in 1987 and worked there as sub-editor, reporter, feature writer and edition in charge. In 1994, he broke the submarines purchase scandal in Daily Jang. Some close friends of Asif Zardari (husband of then Prime Minister Benazir Bhutto) were involved in that scandal, along with some Navy officials. Mir lost his job the day his article was published.

In 1996, Mir became the editor of the Daily Pakistan in Islamabad, making him the youngest editor of any national Urdu newspaper in the history of Pakistani journalism. He lost his job again in 1997, when he wrote an article in the Daily Pakistan about the alleged corruption of Prime Minister Nawaz Sharif. Also in 1997, he joined Daily Ausaf (Islamabad) as founding editor.

Mir spent ten days in the Eastern Afghanistan, where he investigated the escape of Osama bin Ladin from Tora Bora mountains in December, 2001.

In 2002, Mir joined GEO TV as the Northern Region editor. Since November, 2002, he has hosted GEO TV's Capital Talk, a political talk show in which top Pakistani politicians from the government and opposition have appeared. He is currently writing a biography of Osama bin Ladin, as well as a weekly column in Daily Jang and The News.