In 2265 Scott spent his shore leave on Drozana Station. There he became trapped in the Devidian plot to invade the Neutral Zone. Together with an unknown individual he saved the station from being flooded with triolic waves.
Later that year Scott was assigned to his most famous position aboard the original U.S.S. Enterprise. He took part in that ship's famous five year mission under Captain James T. Kirk. After this time he was responsible for the ship's refit. After the destruction of the Enterprise in 2285, he assumed the post of chief engineer aboard the U.S.S. Enterprise-A.
Scott's fate was not discovered until 2369, when the crew of the Enterprise-D found him in the transporter buffer of the U.S.S. Jenolan which had crashed on a Dyson sphere. He was rescued and left the ship aboard a shuttle.
- “Earthward Bound”: In 2270, Scotty congratulates the player on their work, and muses that the player looks familiar. He also discusses the dangers of the inhabitants of Taurus II.
- “Painful Omens”: Scotty is present aboard Deep Space K-13 in 2270 when it is overrun by neural parasites. The player assists him in activating the station's ultraviolet lighting to kill the parasites. From the station, he is able to disrupt the temporal shielding of a Na'kuhl vessel, and is beamed aboard the player's ship before the station is lost through a temporal anomaly.
- “Return to Babel”: The player and Captain Pavel Chekov encounter Scotty aboard the Enterprise in 2268. Scotty is confused by Chekov's older appearance, and remembers the player from Drozana Station. Chekov reveals that he and the player are time travellers, and Scotty helps them save the ship from a Na'kuhl bomb, which they beam to a nearby Orion vessel. Scotty recovers Chekov's temporal transponder, which he mistakenly dropped on the Enterprise.
- “Night of the Comet”: In 2265, Scotty helps the player defeat time-travelling Devidians aboard Drozana Station. He also discusses the possibility of storing a person inside a transporter buffer with Delta Recruits, planting the idea in his mind for the future.
- “Ragnarok”: Having held on to Chekov's temporal transponder for many years until it sent a signal, Captain Scott travels to the 26th Century and helps Chekov and the player during the Battle of Procyon V. Chekov then returns him to the 24th Century...after a brief visit to the 23rd Century.
- “Days of Doom”: Montgomery Scott assists a time traveling player in preventing the Na'kuhl to unleash a Planet Killer to destroy a starbase.
- “Surface Tension”: Upon traveling to the Jenolan Dyson Sphere, Admiral Tuvok tells the player about the incident when the Enterprise-D rescued Scott from the transporter buffers of the Jenolan, which had crashed on the sphere.
- Scott was the second main character of The Original Series to visually appear in Star Trek Online, and the third overall. He was also one of the first characters who was modeled to resemble their actor's likeness.
- Similar to Leonard McCoy and unlike many other major characters, Scotty was not voiced in his original in-game appearances. With the release of Agents Of Yesterday in 2016, Scott is voiced by Christopher Doohan, son of the original Scotty actor James Doohan.
- While he is not mentioned in “Past Imperfect” it is possible that Scott is aboard the Enterprise at the time.
- During the Delta Recruitment Event it was revealed that the player (a Delta Recruit) gives Scott the idea to store himself in a transporter buffer in case of an emergency, in order to ensure that he survives to the 24th century.
- Scott might be deceased by 2409 as the U.S.S. Montgomery Scott is named in his honor.
- Scott's iconic engineering vest is one of several late 23rd-century outfits available in the Dilithium Store.
- Official Blog - Bringing Scotty to STO (May 9, 2016)
- Montgomery Scott at Memory Alpha, the Star Trek Wiki.
- Montgomery Scott at Memory Beta, the non-canon Star Trek Wiki.