Grant was to have died from a fall down an open elevator shaft while in pursuit of Jonas Walker, a suspected killer that the FBI was investigating. He was saved by Trevor Holden who grabbed him as Grant lunged after a dropped cellphone.
There was no adverted death in the second timeline. Instead, Traveler 3468 was transferred to a point in his host's history where he knew he'd be.
3468 Future History
Traveler 3468 followed a vegan diet in the future, as he expressed dislike for cow's milk in his coffee and suggested to Kathryn that they try something vegan for dinner. It's been suggested that this isn't an uncommon diet as Vincent Ingram says that newborn life in the future is rare and precious and Ellis says that he cried when he realised what bacon was.
He was also in a relationship with Traveler 3465 (Carly Shannon), but they thought it was best to follow protocol 2 and so ended their relationship. It also would've been complicated by the fact that Grant (the host) was already married and his traveler needed to keep up appearances.
Before Grant's expected death, he had been married to his wife, Kathryn, for nearly ten years and had been working for the FBI for nearly fifteen, alongside his partner, Walt Forbes. Through memories, it's shown that Grant really loved his wife Kathryn and that they'd thought about having children together but ultimately ended in Kathryn having a miscarriage. (Kathryn)
Grant was investigating some code which had been discovered in the deep web, which led him to the building where Jonas Walker, a shooter, had already been found by the team and taken out. Historically, Grant had died prior to finding Walker. For a brief moment, Grant finds out what the travelers' program is, as the team explains it to him, before traveler 3468 is transferred into his body. (Travelers)
Traveler 3468 (Version One)
After completing their first mission, Grant goes home to his wife and ends up sleeping on the sofa. He meets his wife who makes coffee for him (though he throws it out because it has cow's milk in it) and calls her by her full name, which he hadn't done since their first date.
When Grant is tasked with saving Bishop and himself from a plane crash which historically killed everyone on board, he instead opts to save Kathryn and Bishop instead of himself as Kathryn was only on that plane since she thought that Grant was cheating on her with another woman as a result of Jeff Conniker saying that he cheated. He hides in the tail section, which is the least damaged part of the plane, and is taken away by a team of doctors. He has severe damage to most of his organs to the point that futuristic technology could only just save him. (Bishop) (Kathryn)
While he's being operated on, Grant sees memories from his host which have survived the host being overwritten. The memories show how much he loved his wife and their attempts to have a child which result in Kathryn miscarrying. (Kathryn)
Grant finds out that Kathryn is pregnant with his child after seeing supplements in her bag. (Protocol 4)
Grant checks out a warehouse where four people had been found dead. This leads them to Jacob and eventually Vincent Ingram who Grant perceives as a threat due to all places the travelers had been held while they were kidnapped tracing back to his company. Grant and his team decide to kill Vincent when they hack into his computer and see all the images of beaten up travelers, but a messenger tells them to stand down which they do. (Jacob)
Traveler 3468 (Version Two)
To warn the Director of the collapse of the first attempt, Traveler 3468 went back in time to August 18th, 2001 - the moment when the original MacLaren met Kathryn and prior to the transfer of Traveler 001.
MacLaren encouraged Kathryn to give her current fiancee another chance, preventing himself and Kathryn from ever marrying. At some point during the next month he also visited Samantha Burns to warn her about Helios-685. Finally, on the day of the September 11th attacks, MacLaren broke into Anthony Corrigan's office and sent an email to the Director saying: "Traveler program will fail. Do not send 001." 001 did not arrive, (and if he did, he would've been sent to the person at Anthony's desk but since no one was there this would've resulted in a misfire) and MacLaren looked out the window, waiting for the first plane crash. However, something either changed his mind or distracted in a split second making him run out of the room which left his ultimate fate unknown. (Protocol Omega)
- Grant MacLaren has served the FBI for nearly 15 years before his death. Traveler 3468 attended a celebration for his 15 years of service.
- Traveler 3468 has a perfect shot, as shown when he went to a shooting range with his partner Walter Forbes. Grant MacLaren, the host, didn't which was why Forbes was surprised at the sudden change.
- Travel 3468 has broken most of the protocols at some point.
- Protocol 2: Shown in multiple episodes, especially Marcy, Grace, and Jacob where he talks to other travelers about Shelter 41 and the Faction.
- Protocol 4: Revealed in Protocol 4 that Kathryn is pregnant with Traveler 3468's child.
- Protocol 6: In Travelers, he talked to Victoria Boyd because he didn't know what to do. He broke it again in Room 101 when his team went missing and he asked for her help to find them.
- Grant is one of only two characters who has seen memories from his host. The other character is Marcy.
- Traveler 3468 speaks many languages through the series including English, Romanian, Cantonese, and sign language.