He appeared in the 2002 film 8 Mile, as Papa Doc, Eminem's nemesis.
Mackie would later go on to star as a man who struggles to adjust to the world he's created after becoming a corporate whistleblower and later starting a business impregnating lesbians for a fee in Spike Lee's 2004 film She Hate Me.
In May 2016, he co-starred in the HBO TV film All the Way as Martin Luther King Jr., opposite Bryan Cranston, who was reprising his Tony Award-winning performance as President Lyndon B. In 2002, Mackie worked as an understudy to Don Cheadle in Suzan-Lori Parks' play Topdog/Underdog and won an OBIE Award for his role in Carl Hancock Rux's play Talk.His first starring role in a feature film was in the 2003 independent film Brother to Brother, where he played Perry, a young African-American artist who struggles to adjust to the world as a black homosexual.He starred with Christopher Walken in A Behanding in Spokane on Broadway, which opened February 15, 2010.Mackie also narrated The Best That Never Was, director Jonathan Hock's documentary for the ESPN 30 for 30 series about the Philadelphia, MS native and football star Marcus Dupree.Mackie portrayed the rapper Tupac Shakur in the 2009 film Notorious.
He first played Shakur on Off-Off Broadway (while still at Juilliard) in 2001 in the play Up Against the Wind, which also featured his classmate Thoms.In March 2008, Mackie starred in three plays by playwright August Wilson at the John F.Kennedy Center for the Performing Arts in Washington DC: Ma Rainey's Black Bottom, Fences, and Jitney – all part of "August Wilson's 20th Century", a month-long presentation of ten staged readings of Wilson's "Century Cycle".His second nomination was for Best Supporting Actor at the 2009 Independent Spirit Awards for his role in The Hurt Locker.In 2014, he joined the Marvel Cinematic Universe as Sam Wilson / Falcon, making his first appearance in Captain America: The Winter Soldier, and reprising the role in Avengers: Age of Ultron, Ant-Man, and Captain America: Civil War. High School and the New Orleans Center for Creative Arts (NOCCA) and graduated from the high school drama program at the North Carolina School of the Arts (NCSA) in 1997.In 2002, he was featured in Eminem's debut film, 8 Mile.