It is discovered that Mr. Walker was involved with Becky , the gun in his desk being the same one that killed her .
The group admits that it was a prank to get Mercedes and Owen back for making them stay on campus .
group is discovered that Mr. Walker was involved with Becky , the gun in Owen 's desk being the same one that killed her .
The group admits that it was a prank to get Mercedes and Owen back for making them stay on campus .