Who Killed Verity Murder Mystery

Verity Mom came home with some cookies and cake because it was verity s birthday so he invited his friends and when they were going to have some food and cake the lights started flickering and then it went dark for a few minutes and then when the lights turned on Verity was missing they looked everywhere except the basement and then when they went down the doors locked and then they saw Verity laying down bleeding and they had to figure who the traitor was and escape.