Kaidan Alenko

Kaidan Alenko is a Sentinel in the Systems Alliance and member of the Normandy crew. A cautious and politically savy man who knows how the game is played, he is at heart still a romantic.
=== Early Life and BAaT ===
Kaidan's mother was downwind of a transport crash in Singapore while pregnant with Kaidan. Kaidan's father served in the Alliance military, though he did not serve in the First Contact War. When he was pre-teen, Kaidan's family was tracked down by a company called Conatix Industries with support by the Alliance and "highly encouraged" to join them for Biotic Acclimation and Temperance Training (BAaT) out at Gagarin Station. Kaidan found himself wired in the L2 configuration- a technology unrefined and full of horrific side effects. Kaidan would be lucky- he would "only" get migraines. The parties involved were desperate to prevent interference, and so separated the teens and older children from their families by preventing outside communication by the attendees and convincing their families that the biotics were dangerous.
This isolation bonded the students close together. One of Kaidan's closest friends in what the teens called "Brain Camp" was named Rahna, a charming and intelligent girl.
Conatix floundered considerably- they initially struggled with preventing their subjects from breaking their own limbs, much less creating barriers or other useful biotic abilities. Fearing reaching out the the asari would make humanity look weak before a hostile Citadel Council, Conatix turned to turian mercenaries in secret. This cutting corners would have a disastrous effect- many of the children snapped under the pressure, and a few died. After one of the turians named Vyrnnus deliberately broke Rahna's arm for reaching for her water without biotics, Kaidan lost his temper and accidently snapped the mercenary's neck. As a result, he was expulsed from the program, his friendship with Rahna was permanently damaged, and Conatix folded a few years later with the Alliance papering over all the mistakes made.
Despite this, Kaidan would join the Alliance on his own terms in 2173- in own words, "we (biotics) sure don't go undocumented. Might as well get a paycheck for it". He refused further training and an L3 amp retrofit, and earned several of special commendations, eventually earning the rank of Lieutenant, and being tapped for placement on board the prototype SSV Normandy under Captain David Anderson.
=== Mass Effect ===
In 2183, during their shakedown cruise to Eden Prime, the Normandy picked up a distress call coming from the planet. Acting quickly, Captain Anderson sent Kaidan down with their XO, Commander Shepard and Corporal Richard Jenkins to back up Spectre Nihlus Kryik in securing a prothean beacon from the planet- which was the true reason they were heading there in the first place.
Nihlus went ahead of their ground crew. Shortly after hitting the ground the squad was ambushed by geth, killing Jenkins almost instantly. The two of them fought through the geth and came across the only surviving member of the 212, Ashley Williams. Ashely led the two of them back towards where the beacon had been discovered. As they followed the trail of the beacon, they came across Nihlus' body. A witness claimed that another turian had shown up- someone Nihlus appeared to trust named Saren. As soon as Nihlus put his back to him, Saren killed him. The three soldiers then used the cargo train, following where the witness claimed the beacon had been moved. After disabling the bombs meant to destroy the beacon and the colony at large, they were finally able to secure the beacon. Much to Ashely's surprise, the beacon appeared to be active. Fascinated, Kaidan began to approach, only to be drawn into a security field. Shepard, realizing her crewmate was in danger, used her momentum to knock Kaidan free, but was caught herself. The beacon lifted her up for a few moments before exploding, leaving the Commander unconscious. Kaidan and Ashley carried her back to been seen by the Normandy's medic, Dr. Karin Chakwas. During his debrief, Kaidan took responsibility for getting too close to the beacon and also recommended that Ashely WIlliams be invited to join their crew due to her combat skills. Shepard, along with Ashley and Kaidan would present their story to the Citadel Council, who would not believe their top agent Saren Arterius could be behind the attack.
After they were able to prove Saren's involvement in the attack on Eden Prime, and control of the Normandy was given to Shepard, the Commander would often visit with Kaidan to get a sense of what the crew was thinking and feeling. For a time, Kaidan mistook this sincere interest and friendship as Shepard seeking a romantic relationship with him until the Commander set him straight on the matter. Regardless, Kaidan cautioned Shepard against cutting corners, relating his own past with Vyrnnus and explained that the incident made him realized that aliens were "jerks and saints just like the rest of us".
When the crew went to investigate an signal sent from a STG team on the planet Virmire, they found themselves grounded. Forced to rely on some creative tactics, the salarian Captain Kirrahe came up with a plan to draw fire from Saren's base of operations to allow Shepard to sneak in and disable the AA guns. This would allow them to plant an improvised nuclear bomb at a critical part of the base. Shepard assigned Kaidan to assist the salarians, giving her own squad some words of encouragement. After the bomb is planted, Kaidan, Kirrahe, and the remainder of his men are pinned down by geth. Shepard instructed Ashely to guard the bomb while she went to go assist them. Unfortunately before she could reach them, geth reinforcements arrived at the bomb site, forcing the Commander to choose between Ashley or Kaidan and the salarians. Shepard chose to save the larger group of people, leaving Ashely to guard the bomb until it went off. Kaidan was distressed over the decision, but Shepard reminded him that it was her choice- he does not bear any responsibility.
Kaidan was presumably on board the Normandy when it flew in the Battle of the Citadel. 
=== Mass Effect 2 ===
In September of 2183, the Normandy was attacked by an unknown ship. During the crippled ship's death throws, Kaidan reported to Shepard as she was preparing their distress beacon that their loyal pilot Joker was refusing to evacuate- and that he wasn't leaving either. Shepard firmly ordered Kaidan to assist the rest of the crew and evacuate himself while she went to get Joker. When Shepard went down with the ship, like many of the Normandy crew, suffered survivor's guilt, with Kaidan grieving Jenkins, Ashley, as well as Shepard and the rest of the crew that died on the Normandy.
Kaidan remained in the Alliance and sometime after the Normandy was destroyed, Kaidan was promoted to Staff Commander. Much of his work at this time was well classified, likely due to humanity's new Councilor David Anderson's trust in Alenko and being given special jobs. In 2185, as remote human colonies in the Terminus Systems were disappearing rumors of Shepad being alive reached Kaidan's ears. Kaidan rejected out of hand the part that suggested she was involved with Cerberus due to her past on Akuze and the horrific experiments the Normandy crew had uncovered while hunting for Saren. However, when a tip came that the colony of Horizon might be the next target Kaidan was dispatched to the planet to investigate along with some planetary defense towers. Kaidan received icy treatment from the colonists, who had moved away from Council Space to avoid Alliance oversight or interference. Many of the locals believed the defense towers made them more of a target and resented the large amount of resources taken up by guns that didn't yet work.
Unfortunately for everyone, the tip was correct and the Collectors attacked Horizon with the intent of abducting all the colonists. A resurrected Commander Shepard arrived shortly thereafter and was able to interrupt the wholesale kidnap of the colony as well as drive off the craft using the defense towers. A large number of colonists were taken, but Kaiden escaped their grim fate. He was initially happy to see his old leader, but it quickly turned to anger and distrust over the confirmation that she was indeed working with Cerberus. When Shepard offered to have him come with her, Kaidan flatly refused- telling her that he will always be an Alliance soldier. As Kaidan turned to leave, he warned Shepard to be careful and reiterated that she could not trust Cerberus.
=== Mass Effect 3 ===
Prior to June 2186, Kaidan was promoted again (this time to Major) and was placed in command of the 1st Special Operations Biotic Company, a covert operations unit. When the Arcturus Station went silent, Kaidan was called before Alliance Command to give a briefing at the Vancouver Alliance Headquarters. On his way out he briefly spoke to Shepard, on her way to give her own report after six months of captivity due to the destruction of the Alpha Relay. As she left, her escort James Vega queried Kaidan, surprised that he knew the Commander. Kaidan corrected the marine that he "used to". 
The Reapers attacked Earth shortly thereafter, forcing everyone who could to evacuate. Kaidan joined a newly reinstated Commander Shepard on the Normandy, along with everyone who had been on board at the time her artificial intelligence EDI took control of the ship. Before they left the Sol system, Admiral Hackett redirected them to the Martian Prothean Archives. There, Kaidan grilled Shepard on her involvement with Cerberus as they fought Cerberus soldiers who looked as though they had been "upgraded" using Reaper technology, fearing Shepard was now a puppet for the Illusive Man. The two of them were reunited with Dr. Liara T'Soni, and chased down a Cerberus spy who had stolen the critical anti-Reaper plans the asari had discovered shortly before. When Kaidan confronted the spy, Dr. Eva Core, the woman turned out to be a robotic infiltrator and easily overpowered the biotic. While Shepard was able to disable it, Kaidan was critically injured and was rushed to the Citadel's Huerta Memorial Hospital.
Shepard made a point of regularly visiting Kaidan as he healed and the two gingerly rebuilt a tentative friendship. While he was still in the hospital, he was visited by humanity' current Councilor, Donnel Udina and offered the chance to be made a Spectre. Kaidan and Shepard discussed the opportunity and Kaidan accepted the position toward the end of his recovery.
Kaidan was on board the Citadel when Cerberus assaulted the station. As a Spectre, he was tasked with protecting the Council as they attempted to get to safety. Unknown to Kaidan, Udina was actually a Cerberus traitor, bringing the two friends and Spectres into conflict. Shepard was able to convince Kaidan of the truth to back her. Shepard shot Udina, sparing Kaidan that duty.
Afterwards, Shepard invited Kaidan to return to the crew of the Normandy, a position he gratefully accepted.
== Every One That Asketh ==
As far as Alliance paperwork was concerned, Kaidan was the acting captain of the Normandy after she escaped the blast from the Crucible at the Battle of London at the end of 2186, though the actual capacity of that role was mostly filled by Garrus Vakarian. After four months of repairs and a further month of FTL travel, the Normandy arrived at the Exodus Relay and found it dark. After some brilliant work by Tali'Zorah vas Normandy, she was able restart the relay. On the other side of the relay, Kaidan gave an official debrief to Rear Admiral Hannah Shepard, who informed him that if he had not gone to the Normandy during the war, he would have been assigned to work under her.
While on Rannadril during Evadne's vigil, Shepard suffered a severe psychiatric episode, causing her to be medically relived of duty. As Garrus was seeing to his dying mother and distressed mate, Kaidan did the heavy lifting of much of the administrative duties.
After Garris was officially sworn in as co-Captain of the Normandy with Shepard, Kaidan continued his role of being XO- in actuality this time. 
During the hunt for the Marquis d'Apien, Garrus was ambushed by the other turian and was nearly fatally wounded. Kaidan was instrumental in saving his captain's life by using his biotics to seal the gushing neck wound.