Two idiots in Washington state recently put on ski masks, grabbed a four-year-old kid from a PLAYGROUND, and sped of in a van . . . but it was all part of a YouTube PRANK video.


The kid was their half-brother, so he wasn't actually in danger.  And they CLAIM they made the video to raise awareness about kidnappings.


But when you watch it, it seems like they really just wanted to see how the other kids' parents would react.  Plus they start LAUGHING right after they do it.  Then when they go back to tell them it was a prank, the parents FLIP OUT on them.


And a cop who shows up says he almost SHOT THEM.