[1] Landry attended Harold S. Vincent High School where he averaged 16.1 points, 5.9 rebounds and shot 59 percent from the field as a senior, leading his team to the Division I state title game and earning him a unanimous first-team all-state selection by the Associated Press.

He was traded to the Boston Celtics along with Nate Robinson for Eddie House, Bill Walker, and J. R. Giddens on February 18, 2010.

[7] In November 2012, he was acquired by the Reno Bighorns of the NBA Development League[8] and represented them in the 2013 D-League Showcase Three Point Shootout, finishing in second place.

On March 12, it was announced that Landry had suffered a season ending knee injury and was placed on the inactive list.

[10] Following a 2013 NBA Summer League stint, Landry was signed by the Los Angeles Lakers in September 2013, but was waived on October 25.

[17] Landry was named the Lega Basket Serie A MVP of the 2016–17 season, after averaging a league-high 19.6 points per game.

[19] His wife, Efueko, played basketball at Marquette and has three children: a son, Marcus Jr., and two daughters, Mariah and Makaylah.