I like this one.
"Alex, how can I be a spy?" Tom said.
"Well, first you have to have all your living relatives die. Make sure that at least one of them has connections to MI6. This is the easiest part of it.
"Next, make sure that one of your last relatives die in some horrible accident that wasn't really an accident. Remember, this is an extremely important stage. Make sure Mr. Blunt or Mrs. Jones sees you at his or her funeral, and try to talk to them.
"Now, investigate her 'accident' and be almost killed when you are almost destroyed in the vehicle they were using. Use awesome ninja skills to get out, and you must be caught on camera. Hopefully, they'll see what you did and want to recruit you illegally.
"Next, if someone you don't know calls you, answer it. They'll ask you to go to the bank or store which is their cover, and remember to have someone completely unrelated to you with an expired visa or something that they can use against you to live with you. They'll blackmail you, and remember to accept. Next thing you know, they'll tell you about an assassin who killed said relative and tell you to avoid him.
"Go on the suicidal mission, and be caught in several near death situations, and kill the bad guys in an unusual way. Make sure you meet the assassin and become friends with him, and remember, don't kill him. He'll be a useful asset later on some of your missions later, and he'll send you to a criminal organization. You'll go on your first mission for them, and you can't bring yourself to kill your target, no matter how much you hate them or ruined your life. Later on, join the organization permanently after you choose a successor.
"Good luck getting to be a teenage spy!"
Tom realized that Alex had stopped using the 'him or her' in several places, but he just shrugged it off.
He didn't notice the part where Alex said 'teenage'.
5 days later, Tom's aunt, who was actually a spy for MI6 died.
"We want you to investigate your aunt's death. We believe that Alex Rider was responsible for her death, and if you see him at all, contact us and we'll pick you up. Do not, under any circumstances, listen to him."
Tom suddenly remembered their conversation, and how Alex disappeared a few days ago.
Alex did know what he was doing, after all. And Tom was his successor.
I should be updating Pitch Black feathers (formerly known as On Tattered Wings), but this was just begging to be written.