While the police converged on the Texas School Book Depository in Dallas and doctors at Parkland Hospital began working on the mortally wounded President in Emergency Room No. 1, Lee Harvey Oswald was briskly walking the seven blocks from the depository to the bus stop at Elm and Murphy. At 12:40 p.m. he boarded a bus driven by Cecil J. McWatters. Oswald did not realize it, but a former landlady, Mary Bledsoe, was also on the bus and recognized him immediately. “He looks like a maniac,” she observed.

At just the time that Oswald stepped on the bus, the Secret Service placed a frantic call for a priest to administer the last rites of the Roman Catholic Church to John F. Kennedy.

With all of the police activity in the area around Dealey Plaza, traffic had come to a standstill. At 12:44 p.m., Oswald asked for a transfer, got off the bus, crossed in front of it, and started walking to the Greyhound bus station three-and-a-half blocks away.

As he proceeded, police began broadcasting a description of the shooter based on the eyewitness account of Howard Brennan, a 44-year-old steamfitter who had been watching the presidential motorcade from a concrete retaining wall at the corner of Elm and Houston, with a clear view of the sixth-floor window of the depository building where he saw a man “a couple of times.”. The description matched Oswald (and hundreds of other young men in Dallas). “Attention all squads. Attention all squads. At Elm and Houston, reported to be an unknown white male, approximately 30, slender build, height 5’10”, 165 pounds. Reported to be armed with what is believed to be a .30-caliber rifle.”

A dispatcher ordered police car No. 10 to patrol the Oak Cliff area. The driver was J. D. Tippit, an eleven-year veteran of the force. Dallas police had recently begun experimenting with the new policy of allowing officers to ride alone in cars patrolling low-crime areas. Tippit had voted for Kennedy and he would have liked to have seen him, but he was also relieved to be far removed from the dangerous and high-stakes job of guarding his safety. “10-4,” Tippit radioed back.

At 12:47 p.m. Oswald entered a taxi driven by William Wayne Whaley at the Greyhound bus terminal. Whaley opened the back door for his passenger, but Oswald said he wanted to sit in the front seat—a common practice in the Soviet Union, where the former U.S. Marine had defected in 1959. Oswald told him to take him to the five hundred block of North Beckley. While Oswald was riding in the cab, police once again broadcast a description of the shooter to all cruisers. Whaley, who had not yet heard news of the shooting, asked his passenger about all the police sirens. Oswald did not respond. He rode the entire way in silence. The driver later told investigators he thought Oswald was “a wino two days off the bottle.”

After the two-and-a-half-mile ride Oswald asked the driver to drop him off at Beckley and Neely, about a ten-minute walk from his boarding house. Why not have the driver take him right to his house? Oswald likely feared that police would have already identified him as the killer and were speeding to his room. He wanted to spy the area and make sure it was safe. “This will do,” he said. The driver pulled over to the curb. The fare was ninety-five cents. Oswald handed the driver $1. “Keep the change,” he said.

It took Oswald nine minutes to make it to the rooming house. The housekeeper, Earlene Roberts, had just learned that the president had been shot when she saw the front door swing open and Oswald come in. “Oh, you are in a hurry,” she said. He ignored her comment, moved quickly past her and into his small room to the left of the living room. There were double doors leading into what had once been a small alcove. The room was about five feet by twelve feet with the bed taking up most of the space. An air conditioner occupied one of the four adjacent windows, which were screened by venetian blinds and lace curtains.

Although it was a warm day, Oswald pulled a white “Eisenhower” jacket from the rack, tucked a revolver into the waistband of his pants, and rushed out of the house. He spent a total of four minutes in the house.

During that time, doctors at Parkland Hospital doctors officially declared Kennedy dead. Shortly after 1:00 p.m., attorney general Robert Kennedy received a phone call at his home in Virginia informing him that the wounds his brother suffered proved fatal.

Back at the book depository the supervisor told police that one of his employees was missing. His name: Lee Harvey Oswald.

Oswald left the boarding house at 1:03 p.m., zipping up his jacket to hide his pistol as he walked out the door. Where was he headed? It is clear that his was not a suicide mission. Oswald set up the shooting to allow himself an easy escape (at least as easy an escape as possible from the sixth floor of a building in a crowded downtown area swarming with law enforcement officials). He had a direct frontal shot at the president as the motorcade moved toward the book depository building on Houston Street. Instead, Oswald allowed the car to make the sharp left turn so he could shoot the president from behind, confusing the Secret Service, and allowing an opportunity to escape.

But escape to where? It is impossible to know for sure, but there are a several possibilities. First, there are a group of improbable conspiracy theories. Some have speculated that Oswald planned to meet with his “handlers” at the Texas Theater, where he was to be eliminated as part of a larger plot. Of course, those who maintain Oswald’s innocence accept the version he later told police. He was not in a hurry to go anywhere: he left the building after the shooting because he assumed it would be closed. He went home, grabbed his gun, and went to the theater.

There are a few other scenarios that fall into the same highly improbable category. Some have suggested Oswald was on a broader mission that day and that Kennedy was only his first target. Michigan Congressman Harold Sawyer, a member of the House Select Committee on Assassinations, suggested that Oswald grabbed his handgun at home in order to kill a man who had been identified in the Dallas press as a communist informer. According to Sawyer the man lived only a few blocks from where Oswald later shot and killed officer Tippit during a chance encounter on Tenth Street, just past the Patton Street intersection. There have also been suggestions that Oswald was headed to finish off retired right-wing General Edwin Anderson Walker, whom he had attempted to assassinate in April using the same mail-order rifle used to shoot Kennedy.

A second school of thought, closely associated with those who support the general conclusions of the Warren Commission, maintains Oswald had no plan and was simply improvising. According to Jean Davidson, author of Oswald’s Game, Oswald never even expected to survive leaving the book depository. “He probably assumed that the building would have been surrounded much more quickly than it was and he never would have gotten out of the building alive,” she reflected. Also, he simply did not have time to plan an escape route. Oswald only learned two days earlier that the president would be going past the book depository. If he had given some thought to the escape he would have anticipated that a city bus would have been trapped in the chaos he had created. “A city bus is not the usual means of escape if someone had planned ahead of time,” she pointed out.

Other serious students of the assassination share this view. John McAdams, the creator of a conspiracy debunking website The Kennedy Assassination Homepage, also believes Oswald had not given serious thought to getting away. “It looks to me like he was improvising,” he told the author. “He never expected to get out of the book depository building without being captured or killed.” Thus, once Oswald left the crime scene and managed to get back to the boarding house to retrieve his pistol, he was essentially lost. “He was just walking around Oak Cliff trying to decide what to do before the police caught him,” recalled McAdams.

A third theory supports the Warren Commission’s conclusions but speculates that Oswald had an escape plan. Gerald Posner, author of Case Closed, concluded Oswald likely “had a plan for how to get out of Dallas.” Posner believes Oswald “was on his way back to Mexico City and the Cuban consulate.” This is a view shared by journalist and author Max Holland, who also believes Oswald was the lone assassin.

Oswald “didn’t want to go back to Russia any longer,” Posner told the author in 2012. “He only wanted to get to Cuba, where he thought the real revolution was happening. Cuban bureaucrats in Mexico City had refused him a visa to Havana only a month earlier. He intended to show up and say, ‘This is what I’ve done,’ and they would have no choice but to enthusiastically embrace him.”

Oswald had just enough money in his pocket for a one-way bus trip to Mexico City. In an unpublished draft of the Warren Commission report, counsel David Belin suggested that Oswald was only four blocks from catching a Route 55 bus that would have taken him to Lancaster Road, where he could have boarded a southbound Greyhound bus that would have, with connections, traveled to Monterrey, Mexico.

Just as his motives were complicated, so too were Oswald’s movements after the shooting. It is impossible for any single theory to explain all the contradictions of his actions. If Oswald was planning to take a bus to Mexico, why not take one from the main bus terminal downtown? He did not even enter the building, and instead grabbed a taxi just outside the terminal. Also, he would have needed a visa to cross the border. How was he planning to get into Mexico? Finally, he had enough money to pay for the bus ticket, but how was he planning to survive once he reached Mexico?

There are plausible responses to some of these questions. He likely wanted to avoid the central bus terminal because he assumed the police would be looking for him there; better to get a bus a little farther out of town. The lack of a visa is harder to explain. Maybe he thought he could talk his way over the border. Of course it is just as likely that he believed someone was going to help him get to Mexico City. Given that he had barely enough money to pay for the bus ticket, and that he had left his entire savings with his wife Marina, it would appear that he expected to be taken care of once he crossed the border.

Former CIA analyst Brian Latell believes offers of assistance may have come from Cuban intelligence. If they had been involved with Oswald, they would have either assigned him a dedicated agent in Dallas or a “cut up”—someone personally loyal to Castro but with no official status. A dedicated agent would have been authorized to make promises and provide Oswald with assistance getting out of Dallas and the United States. A “cut up” would have no such official authority, but could still have offered aid. In either case, Oswald would have had support and encouragement from an outside source, and assistance getting across the border.

This explanation still begs the question of why Castro would take the risk of being tied to someone trying to assassinate the President of the United States when he knew it would be suicide if Oswald were caught. Latell speculates that it is most likely Cuban intelligence officers were freelancing; that Castro would not have been aware of their efforts to encourage Oswald to follow through on his threat against Kennedy. It seems unlikely, however, that low-level Cuban operatives would have taken on such a risky operation without Castro’s knowledge, and even less likely the Cuban leader would have sanctioned such an operation. Despite the lack of physical evidence, and the heavy weight of logic against this theory, Latell is highly credible and not easily dismissed as a conspiracy crackpot. If he is right, the elusive final answers to the Kennedy assassination are probably locked away, collecting dust in a secure Cuban intelligence archive.

Excerpted from “Lee Harvey Oswald: 48 Hours to Live,” by Steven M. Gillon. Published by Sterling Publishing. Pick up a copy wherever books are sold.