We are given an “m4v” file. After trying to open it, it errors out. Maybe it isn’t really an m4v file. Let’s open it in HXD, hex editor.
Hey look! There’s something. It looks like it might be a substitution cipher. Let’s copy that and drop it down into:
Bam, That’s the flag. And it happens to be a quote from Mr.Robot which is also hinted at with the name of the file, a name of an episode in Mr.Robot.