Edgar the Bug's skin was brown and his eyes are yellow.
In the film, Edgar was an interstellar terrorist in search of the Arquillian Galaxy and lands on Earth to get it. He was big enough to eat humans, like the farmer Edgar and uses his skin as a disguise. He rampages through New York City as a human, killing people and trashing everything and everyone in his way.
Eventually, he found Rosenberg and killed him and got what he thought was the galaxy but it was diamonds. He later finds that it's on the collar of Rosenberg's cat Orion and infiltrates the morgue to get it. He takes Dr. Laurel Weaver as a hostage and Agents K and J pursue him. Dr. Weaver escapes but Edgar manages to get on one of two working spaceships.
The agents shoot his craft down and hold him at gunpoint, but Edgar rips off his disguise and reveals his true form. He eats the agents' guns and Kay purposely gets eaten as well. Then Jay is able to distract the Bug by stepping on cockroaches, which caused him to get mad. He was defeated by Kay who blasts him from inside with his gun, but half of him was still alive and he was finished off by Laurel with Jay's gun.