Q: (CNN) -- Many have claimed to know the identity of the notorious Zodiac Killer, who terrorized northern California with a trail of unresolved murders in the 1960s. But their stories have not panned out.

Now, a Louisiana man believes he has the definitive answer to the chilling mystery: Who was the crazed, elusive killer who wrote letters bragging about his conquests?

Gary Stewart says it was Earl Van Best, Jr., his biological father, who died in 1984.

"I believe for the first time in the history of this case that I have presented more evidence that has ever been presented on any one suspect," Stewart told CNN's Erin Burnett about his new book.

The Zodiac Killer has been connected to five deaths between 1968-69. Though he was never caught, he gained notoriety by writing several letters to police and newspapers boasting of the slayings. He included swatches of bloody clothing as proof of his claims of killing as many as 37 people.

Stewart's quest for dad

Stewart was born in New Orleans, abandoned as a newborn in a stairwell in Baton Rouge, and later adopted.

About 10 years ago, when he was 39, his birth mother, Judy, contacted him for the first time. He then began his search for his biological father, whom both had not contacted since Stewart was abandoned.

The vice president of a cleaning company in the capital of Louisiana recounted his decade-long search for his biological father, which ended with the discovery that Best was the serial killer.

1. Gary Stewart
2. Earl Van Best, Jr
3. Judy
4. 39
5. He was abandoned as a newborn.
6. He was vice president of a cleaning company.
7. In the capital of Louisiana.
8. In Baton Rouge.
9. The Zodiac Killer.
10. Northern California.
11. 37
12. No
13. Yes
14. No.
15. Yes.
16. To the police.
17. Swatches of bloody clothing.
18. Earl Van Best, Jr.
19. unknown
20. Erin Burnett

Numbered questions:
1. Who tried to find information about his father?
2. Who was his father?
3. Who was his mom?
4. How old was he was she got in touch with him?
5. Why hadn't he had any contact with them?
6. What was Stewart's job?
7. Where did he work?
8. Where was he born?
9. Who was a famous murderer in California?
10. Which part of California?
11. How many people did he definitely kill?
12. Was he captured?
13. Do people think they know who he is?
14. Have any of them been proven right?
15. Did the murderer write letters?
16. To who?
17. What did he include?
18. Who does Stewart think the murderer is?
19. Does he have proof?
20. Who did he talk to about his theory?

Q: CHAPTER XIII

AN AWKWARD POSITION

When Captain Nelson and Terence went out, just as the morning was breaking, they found the two troopers waiting in the street. Each held a spare horse; the one was that upon which Terence had ridden from Coimbra, the other was a fine English horse.

"What horse is this?" Terence asked.

"It is a present to you from Sir John Cradock," Captain Nelson said. "He told me last night that the troopers had been ordered to ask for it when they took your horse this morning, and that his men were ordered to hand it over to them. He wished me to tell you that he had pleasure in presenting the horse to you as a mark of his great satisfaction at the manner in which you had mastered the military details of Sir John Moore's expedition, and the clearness with which you had explained them."

"I am indeed greatly obliged to the general; it is most kind of him," Terence said. "Will you please express my thanks to him in a proper way, Captain Nelson."

They rode to the Treasury, where they found the Portuguese escort, with the mules, waiting them. The officer in charge of the Treasury was already there, and admitted the two officers.

"I have packed the money in ammunition-boxes," he said. "I received instructions from Mr. Villiers to do so."

"It is evident that your words had some effect, Mr. O'Connor," Captain Nelson said aside to Terence. "I suppose that when he thought it over he came to the conclusion that, after all, your suggestions, were prudent ones, and that it would add to the chance of the money reaching Romana were he to adopt it."

1. two troopers
2. in the street
3. just as the morning was breaking
4. yes
5. Coimbra
6. Captain Nelson
7. a fine English horse
8. Sir John Cradock
9. Terence
10. yes
11. provide the English horse
12. military details
13. yes
14. Sir John Moore's
15. yes
16. yes
17. ammunition-boxes18. Mr. Villiers
19. the Treasury
20. the Portuguese escort and the officer in charge of the Treasury

Numbered questions:
1. Who held a spare horse?
2. Where were they?
3. What time was it?
4. Had Terence ridden one?
5. from where?
6. Who else was with Terence
7. Which horse was the present?
8. From who?
9. to who?
10. Had the troopers been ordered?
11. What were they ordered to do?
12. What had Terence mastered?
13. Were they of an expedition?
14. Whose?
15. Did he explain them?
16. Was the money packed?
17. What was it packed in?
18. Who did he receive instructions from?
19. Where did they ride to?
20. Who was there?

Q: John once told me a story about his friend, Michael. Michael happened to be on a train sitting next to a young man who seemed worried. Finally the young man told the friend that he was a convict returning home from a prison far away. What he did had brought shame on his family, and they had neither visited him nor written to him. He hoped, however, that this was only because they were too poor to travel and too busy to write.

When he was set free he had written to tell them he wanted to go home. To make matters easy for them, however, he had asked them to put up a signal for him when the train passed their little farm. If the family had forgiven him, they were to put up a white ribbon in the big apple tree near the railway. If they didn't want him back, they were to do nothing, and he would stay on the train, and go far away.

As the train neared his hometown his _ became so great that he was afraid to look out of the window. He asked Michael to watch for the big apple tree. They changed seats. In a minute, Michael put his hand on the young convict's shoulder, "There it is," His eyes was filled with sudden tears. "It's all right. The whole tree is white with ribbons."

1. Michael
2. yes
3. anapple tree
4. ribbons
5. he thought they might be ashamed
6. a young man
7. a convict
8. because of what he did
9. no
10. put up a white ribbon in the big apple tree near the railway
11. by train
12. by letter
13. that they didn't want him back
14. unknown
15. to look out of the window
16. to watch for the big apple tree
17. They changed seats
18. he would stay on the train, and go far away.
19. they were to do nothing
20. on the young convict's shoulder

Numbered questions:
1. who was he sitting next to?
2. Did the story have a happy ending?
3. what tree was it?
4. what did it have?
5. why did he think the family didn't visit?
6. who was he?
7. and?
8. how did he bring shame?
9. was the prison near home?
10. what were they to do if they forgave him?
11. how was he traveling?
12. how did he communicate?
13. what was he scared of?
14. and?
15. what was he afraid of?
16. what did he ask michael to do?
17. and what did they both do?
18. what would he do if they didn't forgive?
19. what were they to do if they didn't forgive?
20. where did Michael put his hand?