He is best known for his work on the series The X-Files (1995-2002) and its spin-off The Lone Gunmen (2001), and as the developer/creator of The Man in the High Castle (2015-19),[2] Medici (2016-19), Ransom (2017-19), and Leonardo (2021) Spotnitz is also the chief executive officer and founder of Big Light Productions, a London- and Paris-based production company, which specializes in international television series, including drama, comedy and documentaries.

Spotnitz's career includes creating, writing and producing series with networks, cable, streaming and other broadcast platforms around the world.

[8] Spotnitz graduated from the University of California, Los Angeles (UCLA) with a bachelor's degree in English literature in 1982, where he was a reporter for the Daily Bruin.

[10] He directed two episodes and wrote or co-wrote more than 40 instalments of the series, including the Emmy-nominated "Memento Mori" with Chris Carter, Vince Gilligan and John Shiban in 1997.

In 2012, Spotnitz created, wrote and executive-produced the international spy drama series Hunted for BBC1 and HBO/Cinemax, starring Melissa George, Adam Rayner, Stephen Dillane and Patrick Malahide.

Spotnitz created, executive-produced and wrote several episodes of The Man in the High Castle,[12] based on the classic alternative history novel by Philip K. Dick, which upon its release became Amazon's most viewed series ever.

[13] Starring Alexa Davalos, Rufus Sewell and Joel de la Fuente, the series explores life in a 1962 America where the Allies lost the war and the country is divided between the fascist Japanese in the West and the Nazis in the East.

[15] Spotnitz co-created, executive-produced and co-wrote Medici: Masters of Florence, starring Richard Madden, Dustin Hoffman and Annabel Scholey.

[17] The Netflix Original Series was produced with Lux Vide Productions for RAI, Italy's largest broadcaster, and SFR in France.

[19][20] Set 20 years later, Medici: The Magnificent starred Daniel Sharman, Bradley James and Sean Bean, and was also co-created, executive-produced and co-written by Spotnitz.

It starred international comedy sensation Russell Peters, whom Forbes magazine ranked three times in its Top 10 highest-grossing comics list.

Peters portrays Doug D’Mello, a charming, smart Toronto cop, who unexpectedly finds himself investigating murder in his parents’ Indian homeland, where, despite his heritage, he remains an outsider.

Canada's biggest series debut in two years was the second-most watched programme on the day of its CTV premiere, with 1.6 million viewers.

[27][28] The series was released in early 2021 in RAI for Italy, Amazon Prime for the United Kingdom and Ireland, as well as Sony LIV in India, and PikTV in Canada.