A Roylan, Keenser originated from the planet Royla. He was larger than most Roylans, which led to a degree of mockery from them. When the USS Kelvin made contact with his people in 2230, Keenser was able to demonstrate an exceptional degree of engineering skill to the First Officer, Lieutenant Commander George Kirk. He chose to join the ship when it left the planet, the first of his people to travel into deep space. He suffered from space sickness during his first journey. [2]Keenser left the Kelvin before it was destroyed in 2233, and by 2258 he was Montgomery Scott's assistant on the Starfleet Delta Vega outpost. Keenser rarely spoke, but according to Scotty he was notable for his very small appetite. When Scotty was promoted to Chief Engineer on board the Enterprise Keenser joined the ship as an engineer. [1]Keenser and Scotty had a close relationship. When Mr Scott resigned his post as Chief Engineer of the Enterprise in protest at the military strike mission assigned to the ship in 2259, Keenser left with him. The two were also to be found socialising together whilst on Earth. [3]He returned to the Enterprise with Scotty and remained on the ship during its 5 year mission of exploration, becoming one of those captured by Krall in 2263. Keenser was suffering from a cold at the time, and was able to sneeze a large quantity of highly corrosive mucus onto the lock of his cell, facilitating a brief escape for Sulu and Uhura. [4]