for almost five hours they 'd studied the mail , and they were now almost certain that ( a ) the laptop letter was a fake , with the name `` al '' signed by someone who was quite good at forging ; ( b ) the forged `` al '' signature was virtually identical to the original `` al , '' so the forger at some point had gained access to ricky 's correspondence with al ; ( c ) the notes to ricky and carol were handwritten by aaron lake ; and ( d ) the one to carol had obviously been sent to them by mistake .