I dont think oj acted alone killing 2 people?

i find it hard to believe that one person did this. he is not a trained killer.how does one guy get 2 people to step out side, so he can cut there throats, with out a fight.he must of had help. and it was a small area to work in no room to hide. i just saw the crime seen photos. iam not saying he didnt do it i am just say he must of had help