Viewed as a versatile linebacker prospect, Plummer was given a three-star rating from Rivals, ESPN and Scout.

On September 5, 2015, he was waived during final roster cuts before the start of the regular season,[3] but signed to the team's practice squad the next day.

[12] On October 17, 2016, Plummer signed a practice roster agreement with the Toronto Argonauts of the Canadian Football League.

During the playoffs, Plummer recorded an interception, which he returned for a touchdown to help Toronto win the CFL East finals and advance to the 105th Grey Cup, in which the Argos defeated the Calgary Stampeders.

[13] Plummer was signed to a contract from the rights list of the Orlando Apollos of the Alliance of American Football (AAF) on April 1, 2019, the day before the league suspended operations.

[14] Plummer was signed by the Hamilton Tiger-Cats of the CFL on April 4, 2019, after the AAF suspended football operations.

[15] In October 2019, Plummer was selected by the Tampa Bay Vipers in the open phase of the 2020 XFL Draft.