On November 29th, 2015, Sam Pepper uploaded a video titled "KILLING BEST FRIEND PRANK". In this video, he mentions that five weeks prior to filming, he met a pair of Viners, and was inviting them over to talk about a video project. He then reveals that his intention was to prank them, by seeing "how [Sam Golbach] reacts to seeing his best friend of five years being killed in front of him".

Sam Golbach's "friend", Colby Brock, was in on this act, and lured his friend in to get kidnapped by Sam Pepper. As Pepper threw a black pillow case over Golbach's head, Brock pretended to get dragged away before running over to help Pepper restrain and bind his screaming "best friend", who was crying out his name and begging for someone to help him while struggling for his life.

The video later cuts to a rooftop in Downtown LA, where Golbach is restrained to a chair, and threatened with an apparent gun to his head. Brock is shown to have tape over his mouth, at which point Golbach tries to tell him "it's going to be alright". As Pepper holds the gun to Brock's head, Golbach begins screaming for him not to, saying "Please, don't." and "We're just kids from Kansas".
As Golbach yells, "He's everything I have", Pepper pulls the trigger, and Brock falls over, pretending to be dead. The audio is then silenced and replaced by piano music, but Golbach can clearly be seen screaming and sobbing as Pepper's camera zooms in on his face.

After a few minutes of this, Brock stands up and tries to calm him down, grinning and laughing as Golbach sits with a confused and terrified expression. As music replaces the audio once more, Golbach can be seen saying things like "What?" and "What the fuck", and Brock begins pulling of the tape holding Golbach to the chair.
As the camera is picked up and moved closer to the two, Golbach stares in shock before sobbing again. Brock grins at the camera triumphantly before the music fades out and Golbach can be heard saying "I actually thought you died, don't ever do that again", and clings to Brock.

Even though Golbach claims to be okay in the video's outro, that does not change the fact that what these boys did is a crime.
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But that's not all that Sam Pepper has done, not is it the first time he's kidnapped someone.
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In 2014, several women filed reports that Sam Pepper sexually assaulted them. While he does (in some cases) deny physically interacting with these women in an inappropriate manner, he did try to play it off as a "social experiment". To elaborate, Sam Pepper has posted several videos of him "pranking" women by grabbing or pinching their bottoms as he walked past them, or poking them with fake hands or fingers. He has also handcuffed himself to unknown women in public, demanding they kiss him or else he wouldn't uncuff them. While he eventually made a video showing him grabbing male butts to try and "balance it out", it still stands there are far more videos of him sexually harassing and objectifying women. Not to mention, he has also made women he is close to feel bad about themselves, by calling them sluts and whores, and making them feel like terrible people for rejecting his advances.
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Sam Pepper has stated multiple times to several people that he doesn't see anything wrong with what he is doing, and intends to continue this behavior. With the recent escalation from sexual assault to kidnapping, it is likely that Sam Pepper will only become more and more outrageous. He is a danger to the community, and needs to be stopped before someone gets seriously hurt by his actions.

Sam Pepper needs to be arrested now.