Dellums has had parts in television police dramas such as "New York Undercover", ' (in which he played drug kingpin Luther Mahoney), and "The Wire" (in which he played a medical examiner). He also played the doctor in "Homeland" season 3, episode 3, "The Tower of David" (as Erik Todd Dellums). Dellums provided voice acting for the 2008 video game "Fallout 3" as Three Dog. He provided the voice of Nazir, a character in the video game '. In 2013, he provided the new voice of Nasus, a champion in the video game "League of Legends", after original voice actor Eugene McDaniels passed away. Dellums narrates the Travel Channel series "Mysterious Journeys", as well as the documentary television series "How the Universe Works" and "NASA's Unexplained Files" on the Science channel. Dellums narrates the Science series "The Planets" – hosted by former astronaut Mike Massimino and retitled "The Planets and Beyond" for its second season in 2018 – which premiered in 2017.