Lieutenant Commander Airiam was a female Human cyborg, a Starfleet science officer who lived during the mid-23rd century. Beginning in 2256, she served aboard the USS Discovery as the spore drive ops officer. (DIS: "Context Is for Kings", "The Butcher's Knife Cares Not for the Lamb's Cry")
Following the aftermath of the accident, Airiam received cybernetic augmentations. One side-effect of her augmentation was the requirement to manually manage her memories, choosing for each individual memory whether to delete it or archive it. (DIS: "Project Daedalus")
Service aboard Discovery
During a battle with the Klingons to save Corvan II, Airiam managed the ship's excess energy cavitation and maintained contact with Stamets and engineering, apprising the bridge when the spore drive was ready to use for escape. (DIS: "The Butcher's Knife Cares Not for the Lamb's Cry") She frequently maintained communication between the bridge and the spore drive engineers during critical situations. (DIS: "Choose Your Pain")
Lieutenant Commander Airiam was one of the higher-ranking bridge officers, and, as such, was occasionally left in command when Captain Lorca and Commander Saru were away from the bridge. After Lorca's death, she held the bridge while Saru met Michael Burnham in the transporter room following Discovery's return from the mirror universe. (DIS: "The War Without, The War Within", et al.)
The red bursts
Airiam was at her post on the bridge when Discovery responded to a distress call by the USS Enterprise. She was among the bridge officers present to witness the transfer of command codes when Captain Christopher Pike took command to investigate the red bursts, and identified herself as part of a bridge officer roll call Pike ordered (the only one who stated her rank, despite orders to the contrary). Later, preparing for the deployment of a gravity simulator to capture a fragment of an interstellar asteroid, she coordinated communication from the shuttlebay to the bridge and confirmed they had a flux coupler ready. (DIS: "Brother")
Airiam was involved in the use of the spore drive during the mission to Terralysium, (DIS: "New Eden") and again for the mission to rescue Sylvia Tilly from the mycelial network. (DIS: "Saints of Imperfection")
Working together with Sylvia Tilly, Airiam was instrumental in sorting through the hundreds of thousands of years of information transmitted to Discovery's computers by a mysterious sphere lifeform. According to Tilly, the task would have taken months without Airiam. (DIS: "An Obol for Charon", "The Sound of Thunder")
Corruption and death
In 2257, her cybernetic parts became infected by an unknown entity from the 28th century; any time it would assert control over her, an inverted pyramid of three red dots would flash in each eye. (DIS: "Light and Shadows")
This infection led to Section 31's threat assessment system, Control, taking over her motor functions in an attempt to upload the hundred thousand years of information the entity dubbed "Sphere" had collected on artificial intelligence in an attempt to gain full sentience and, as believed by the crew of the Discovery, fulfill the vision Spock was shown by the Red Angel.
She was able to upload 25% of the data before Michael Burnham and Nhan intervened. Burnham was able to lock Airiam in an airlock in the course of the fight. After an attempt by Burnham to save Airiam by deleting the data Airiam had uploaded failed, she – at her insistence, in a moment of lucidity – was ejected into space by Nhan. She subsequently froze due to exposure, causing her systems to shut down. (DIS: "Project Daedalus")
Prior to her away mission to the Section 31 base and subsequent death, she uploaded the majority of her personal memories to the Discovery's database. (DIS: "Project Daedalus") Her body was retrieved by the crew, who held a funeral for her in the shuttlebay before releasing her torpedo casket into space. (DIS: "The Red Angel")
Aboard Discovery, Airiam was popular among the bridge officers. She was particularly close friends with Sylvia Tilly, Keyla Detmer, and Joann Owosekun. The four of them enjoyed playing kadis-kot together, though Owosekun poked fun at Tilly and Airiam for having memorized every possible gambit. Detmer later joked "don't forget about us little people," when she envied Airiam's assignment to an away mission.
Even until late 2257, Airiam kept some of the details of her life before her accident private, only sharing them with Tilly a few days before her death.
In reviewing her memories, Airiam also held fondly time spent looking out a window into space with Michael Burnham who she considered a friend. Their friendship over the course of Burnham's time aboard Discovery made it all the more difficult and painful for Burnham to grapple with having to eject Airiam into space when Airiam's corrupted-augmentation threatened the entire crew.
In the week prior to her death, she also saved a fond memory of sparring with Lieutenant Gen Rhys, where she was able to get the upper-hand on him. As Airiam was speaking her last words over the comm, Rhys stepped over to Detmer to put a hand on her shoulder as the two started to tear up. (DIS: "Project Daedalus")
- "Context Is for Kings"
- "The Butcher's Knife Cares Not for the Lamb's Cry"
- "Choose Your Pain"
- "Magic to Make the Sanest Man Go Mad"
- "Si Vis Pacem, Para Bellum"
- "Into the Forest I Go"
- "Despite Yourself"
- "What's Past Is Prologue"
- "The War Without, The War Within"
- "Will You Take My Hand?"
- "New Eden"
- "Point of Light"
- "An Obol for Charon"
- "Saints of Imperfection"
- "The Sound of Thunder"
- "Light and Shadows"
- "If Memory Serves"
- "Project Daedalus"
- "The Red Angel"
- "Such Sweet Sorrow, Part 2" (archive footage)
Airiam was played by Sara Mitich in the first season and by Hannah Cheesman in the second season. Discounting occasions in which characters have been recast due to meaningful changes in the character's appearance, e.g. story lines set in alternate or earlier time frames, she is one of the few ongoing supporting characters to have changed actors. Airiam is also a rare example of a Discovery bit part that became a supporting character, even though it happened in the very episode where she was killed.
Airiam's nature was initially subject to a number of divergent background statements. StarTrek.com described Airiam as being a "synthetic-Human hybrid,"  while Ted Sullivan tweeted that she was an alien.  Meanwhile, AT: "The Butcher's Knife Cares Not for the Lamb's Cry" described her species as "augmented alien," while AT: "Lethe", involving Gretchen J. Berg, Neville Page, and Glenn Hetrick, called her, instead, an "augmented Human." That term was also used by the second Airiam actor Hannah Cheesman and ultimately confirmed on screen.