Larma D'Acy was a female human who held the rank of commander within the Resistance's ground forces. This paramilitary organization was established by Leia Organa with the purpose of monitoring and opposing the actions of the First Order.
Originating from Warlentta, she was personally recruited by General Leia Organa, who held her homeworld's spirit of independence in high regard. Despite Warlentta's decision not to align itself with the New Republic, D'Acy's father was a vocal critic of the demilitarization efforts enacted by the Galactic Senate. D'Acy, coming from a family with a strong military history responsible for the protection of the Warlentta system, joined the Resistance with the full support of her family.

After attending Han Solo's funeral, D'Acy was stationed on the bridge of the Resistance flagship, the MC85 Star Cruiser Raddus, during the evacuation of D'Qar. Subsequently, she was present during the surprise attack on the fleet when the First Order managed to track them through lightspeed by unknown means. Although the bridge was destroyed by TIE fighters during the assault, D'Acy survived because she was away on an errand. She then delivered a report on the situation to the surviving Resistance members on the secondary command bridge, sharing the sole piece of positive news: Leia was alive, though unconscious. With sorrow, D'Acy announced that most of the Resistance Command, including Admiral Gial Ackbar, had died in the attack. Following the line of succession, Vice Admiral Amilyn Holdo, the commanding officer of the cruiser Ninka, assumed leadership of the Resistance.
D'Acy remained loyal to Holdo, which led to her being held at gunpoint alongside Holdo and other officers when Captain Poe Dameron, disagreeing with Holdo's strategies and perceived lack of transparency, initiated a mutiny. Holdo regained control of the ship with the help of Leia, who had recovered and personally stunned Poe. He was then placed on a U-55 orbital loadlifter, which Leia and D'Acy used to evacuate while Holdo remained behind to pilot the Raddus. D'Acy expressed her hope that the plan would succeed. Upon Poe regaining consciousness, D'Acy explained that they were en route to an old rebel base located on the mineral planet of Crait, where they could seek refuge and transmit a signal to their allies in the Outer Rim. As the transports were attacked, Holdo's heroic sacrifice of ramming the First Order fleet at lightspeed was the only thing that allowed the remaining ships to reach the planet's surface safely.
Once they arrived, D'Acy used an old computer monitor to reactivate the base's shields and watched the battle against the First Order unfold. Despite the signal sent by Lieutenant Kaydel Co Connix reaching multiple recipients, it went unanswered, leading D'Acy to realize that their allies had heard them, but no one was coming to help. D'Acy then witnessed the arrival of what appeared to be Luke Skywalker, who confronted the First Order, allowing the Resistance to escape through an underground tunnel aboard the Millennium Falcon. As one of the few remaining Resistance members, D'Acy told C-3PO that she had a contact in the Outer Rim who could provide assistance once they arrived.

Larma D'Acy, a fair-skinned human female with blonde hair and a distinctive nose, was known for her calm and composed demeanor. She rarely lost her composure and remained level-headed even in stressful situations. D'Acy was a dedicated member of the Resistance, loyally following Vice Admiral Holdo and attempting to mediate when Holdo and Poe Dameron clashed over strategic decisions. Despite being deeply affected by the loss of Admiral Ackbar and Leia's near-fatal experience, D'Acy remained determined and resolute.
D'Acy was married to Lieutenant Wrobie Tyce, another member of the Resistance. They shared a kiss following the Battle of Exegol, which marked the end of the war between the First Order and the Resistance.
Larma D'Acy wore the standard Resistance officer uniform, which included a rank plaque indicating her position as Commander, as well as boots and a belt that held a standard-issue Glie-44 blaster pistol.
Amanda Lawrence played the role of Larma D'Acy in Star Wars: Episode VIII The Last Jedi and Star Wars: Episode IX The Rise of Skywalker.