"Melvin Brother of the Joker" is not good, but it's not terrible, at least in my opinion. It's about a guy named Melvin, played by Doug Walker, who is indeed the brother of the Batman villain the Joker. Melvin looks specifically like the Joker from "The Dark Knight"... well, mostly. He's not wearing white makeup. Anyway, he talks to the camera because he's making a video blog. He lives with his mother, who's off-screen throughout this film/sketch, but you hear her yelling at Melvin. Dear God, whoever voiced this mother (I don't know if it was Doug) did a terrible job. She's very annoying and not funny. I hated this performance. Maybe you're supposed to find the mother as irritating as Melvin does, but she could've at least had a better voice. Melvin talks about rayguns and, at one point, talks on a cellphone to someone. I didn't really care. Well, at least Melvin's voice isn't annoying.
There are maybe a couple of moments that are a little funny, but even right after watching "Melvin Brother of the Joker", I don't remember what they are. I mostly wasn't laughing. Still, Doug's performance of Melvin isn't bad, I guess. There's a song at the beginning and at the end. It's a bit catchy. About ten years after this film/sketch was released, "Joker", starring Joaquin Phoenix, was released. That film's title character also lives with his mother, which is kinda interesting. It might be a coincidence. The cinematography of "Melvin Brother of the Joker" is so-so. The editing is fine. Like I wrote, it just isn't funny. It's also kinda cringeworthy. I can't recommend it, unless you wanna annoy somebody.