Marcus is a character in the 3 Ninjas film. He is one of Fester's buddies along with Hammer. He and his buddies try to help Mr. Brown and Snyder by kidnapping the young ninjas to case Sam Douglas and the FBI from taking any further actions against their plans. He can't talk. He was calling "Dude."
Snyder arranges to kidnap the boys. Mr. Brown suggests to him that he knew someone who can help and has help on several prior missions they've had and that he was a relative of his. Snyder tells Mr. Brown to make the call for him and hire his surfer nephew Fester and his friends Hammer and Marcus. During the night they try to kidnap the boys but their father comes home with a few of his colleagues so they're forced to withdraw the attempt. The next morning as the boys ride their bikes to school, Fester and his crew fail to grab them. The boys are at home with a sitter when Fester, Marcus and Hammer show up. Fester and his buddies jump on the pizza delivery guy and Fester poses as him in order to have a reason for entry. The kidnappers subdue the sitter and lock her in a closet. Colt sees them subduing their sitter and their guns and tells his brothers. The boys decide if they can take care of Fester and his gang themselves, then their ninja training would be worthwhile. Using booby traps and their ninja training, they weaken the intruders. After the boys' weaken the intruders, they go to the boys' room and figure out how to lure one of their contacts at which they take captive. They contacted Emily by way of attempting to imitate Rocky's voice but it successfully works with Emily half asleep and less aware. They hold Emily captive at the door. They bring Emily to the door of the study room as captive with a gun. Colt's trick with the instant diarrhea works on Hammer and Marcus leaving Fester alone with Emily. Fester is subdued by Emily while they have gone to the bathrooms and his buddy Hammer is finished off by Rocky and Colt. After helping Emily with Fester, Tum Tum finds Marcus in the downstairs bathroom. As Marcus tries to come out, Tum Tum awaits him with one of the animal trophies. Tum Tum rams Marcus into the bathroom wall. He finishes him by ramming him right into the sternum. Fester eventually calls his uncle for backup. So his uncle, Rushmore and several ninjas arrive at the house to kidnap the Douglas boys. Eventually Snyder is defeated and all of the ninjas are arrested. It is unknown if he and his friends were arrested as well, or if he and his friends got away.