He was portrayed by Erick Hayden.
Marshall was only seen during the SPECTRE meeting in Rome, where he hears of Moreau's reports of the attacks on Hamburg and Indonesia as part of Blofeld's plot to take control of the world's intelligence systems through Max Denbigh's Nine-Eyes program. He would later hear of Dr. Vogel's reports of human trafficking and prostitution.
After Vogel finishes her report, Moreau announces to anyone who would like to fill in for the late Marco Sciarra to kill Mr. White after the failed mission in Mexico, to which Guerra offers to take over. Blofeld then asks if anyone else wants to take over the mission, to which Mr. Hinx arrives on cue.
Marshall then watches as Hinx kills Guerra to ensure that he would do the job pretty well of tracking down Mr. White. Eventually, Blofeld detects James Bond's presence and exposes him, forcing a nervous Bond to escape after killing Lorenzo.
It is unknown what happened to Marshall and the other council members following Blofeld's arrest at the end of the film, though it can be implied that they are still at large.