Collected here is every line of Phasma dialogue which I could find at the time of writing this. If I am missing any lines from The Force Awakens, Before the Awakening and Poe Dameron #2, let me know!
Phasma's speech patterns are precise and educated, bordering on formal. In all situations except her short period as a hostage on Starkiller, she projects self-assurance. Arguably, she is fully aware of this effect, and using it intentionally.
When issuing commands to her stormtroopers, Phasma's speech is firm and to the point, with none of speechifying or emoting of Kylo Ren or Hux, but instead calm, collected, and very sure. This reinforces her authority with the stormtroopers she commands as well as reassure them. She does not explain or discuss how she feels about her commands, she simply commands. See: "On my command, fire." , “I am sending a unit to relieve you. Once they arrive proceed with your team to level alpha-seven-seven, room ought-three. Confirm.” and "Kill them.".
When speaking with her superiors, she speaks more deferentially, often standingly silent until her input is requested or necessary.
By First Order standards, Phasma appears to be quite good at reading people, and this seems to be a part of her job. In Before The Awakening, General Hux relies upon her to be familiar with the performance and psychological state of FN-2187 (soon to be Finn), and she is. See: “But his decision to split the fire-team and return for FN-2003 is problematic. It speaks to a potentially… dangerous level of empathy. You heard him.”
Furthermore, Phasma has been keeping track of her troopers, and in The Force Awakens notices that FN-2187 almost certainly did not fire on the villagers on Jakku, and has become troubled and unreliable, which is why she sends him to reconditioning. Phasma is intimately involved in her troopers' simulation training. She corrects them if she feels they are out of line, and informs them of what she believes are their strengths and weaknesses in a firm, clinical, but judicious manner that seems calculated to inspire troopers to seek her approval and live up to her standards. She does not shy from giving measured praise when she feels it is deserved. It is reminiscent of an amused but distant teacher or military training officer. See: “Rather than fixing the problem, you are allowing it to persist. As a result you are, in fact, weakening the whole. Further, you are weakening yourself.” and "I was concerned about you, FN-2003. I am glad you’ve proven me wrong.”
Phasma's affect is detached, but not unemotional. It is usually flavored by distant amusement, disdain or professional interest. See: "And who gave you permission to remove that helmet?", "Do you think the Supreme Leader would have hesitated, FN-2187?” , "I do not understand why you keep these... people, Agent Terex." and “I have given your request the thought it deserves. Kill them.” or her line reading on "Sir, the villagers," as she reminds Kylo Ren to command her to murder a village.
When relaying orders to and speaking with Agent Terex, a former stormtrooper who has become an Agent of the First Order, we see how Phasma relates to a relative equal who she does not like. She is cutting and superior in tone, relying heavily on implied insult but with no attempt at subtlety. It is almost Dowager Duchess as Stormtrooper Captain in style. See: "I do not understand why you keep these... people, Agent Terex." and "Yes, Terex. Every officer in the First Order knows exactly where you came from. That is why we say it."
Whether Phasma is scorning Terex because he has come up through the ranks - suggesting that she has not; because he has come up from the ranks and refuses to let anyone forget it - instead of adapting to expectations of his rank; or because the stormtroopers are where he came from - that is, he has chosen to leave Phasma's favored world of stormtroopers for a more self-driven, less disciplined life as a First Order Agent; is unclear.
Depending on one's interpretation of Phasma's capture and interrogation on Starkiller, she is either revealed to be a blustering coward when the chips are down, or - for whatever reason - Phasma is putting up a show of outrage and not actually trying to resist very hard. See the wavery and unconvincing bluster on: "You can't be so stupid as to think this will be easy. My troops will storm this block and kill you all." It's a very unusual line reading on the part of a very fine actress, which certainly lends itself to speculation.
In conclusion, I invite you to read and analyze the collected dialogue transcript below, and draw your own conclusions!
The Force Awakens
Sir, the villagers.
On my command, fire.
FN-2187, submit your blaster for inspection.
And who gave you permission to remove that helmet?
Report to my division at once.
FN-2187 reported to my division, was evaluated and sent to reconditioning.
This was his first offense.
You're making a big mistake.
You can't be so stupid as to think this will be easy. My troops will storm this block and kill you all.
Before the Awakening
“Simulation objective completed. FN-2187, FN-2199, FN-2000, FN-2003, report for evaluation and debriefing.”
“They completed the objective due to the skill of FN-2187’s leadership.”
“If that’s why he’s doing it, General.”
“These stormtroopers will be the finest the First Order has ever produced,”
“I have overseen their training at every stage, from induction to deployment. This class is exemplary.”
“Not for this class.”
“FN-2187,” Phasma said, “has the potential to be one of the finest stormtroopers I have ever seen.”
“But his decision to split the fire-team and return for FN-2003 is problematic. It speaks to a potentially…dangerous level of empathy. You heard him.”
“Yes, sir. While I am entirely in support of unit cohesion, General, a stormtrooper’s loyalty must be higher, as you know. It must be to the First Order, not to one’s comrades.”
“FN-2000, you’re wasting ammunition,” Phasma continued. “Telemetry indicates you expended one hundred and twenty-seven shots, with a hit ratio of less than five to one. You are assigned to the range tomorrow during your second detail. I expect an immediate and marked improvement.”
“FN-2199, biosensors noted your heart rate eight percent above acceptable range, with an additional twenty-second delay in reverting from strong exertion to resting pulse. Your weight is up two percent, without corresponding gain in muscle mass. Your meals are being modified, and you will begin additional physical training tomorrow, second detail.”
“FN-2187, your targeting was exemplary. According to the simulation, you fired your weapon only thirty-six times, scoring kills with thirty-five of those. You deployed one explosive, which resulted in the achieving of the objective and another six enemies killed.”
“All of you should take your example from FN-2187,” Captain Phasma said. “You are dismissed. FN-2187, stay.”
“Why did you go back for FN-2003?” Phasma asked.
“This is not the first time you’ve helped him. Your instructors have noted multiple occasions where you’ve been seen assisting him in various duties. Why are you doing this?”
“I want it to stop.”
“We are only as strong as our weakest link, FN-2187. While you believe you are attempting to strengthen that weak link, I assure you that is not what you are actually doing. Rather than fixing the problem, you are allowing it to persist. As a result you are, in fact, weakening the whole. Further, you are weakening yourself .”
“You have great potential, 2187. You are officer corps material. Your duty is to the First Order above everything. Nothing else comes before that. FN-2003 must stand or fall on his own. If he stands, the Order is strengthened. If he falls, the Order is spared his weakness. Am I understood?”
“I sense hesitation.”
“Then it will stop.”
“Then that is all. You are dismissed.”
“I have one question for you, FN-2187.”
“Were you toying with FN-2003? Was that what I saw?”
“I see.” Her helmet turned toward him, hidden eyes seeking his, and suddenly FN-2187 felt horribly exposed standing in the briefing room in his armor, with his helmet tucked under his arm, just the two of them. “You didn’t want him fighting someone else, someone who wasn’t…sympathetic to his situation.”
“Your objective was simple, FN-2187.”
“But you considered losing to him first, didn’t you?”
“A real stormtrooper has no room for sympathy,” Phasma told him. “A real stormtrooper is the extension of the First Order, of Supreme Leader Snoke’s will, nothing less. Do you think the Supreme Leader would have hesitated, FN-2187?”
“Gather your fire-team,” Phasma said. “You are being deployed.”
“FN-2187, respond.” It was Phasma’s voice.
“I am sending a unit to relieve you. Once they arrive proceed with your team to level alpha-seven-seven, room ought-three. Confirm.”
“The negotiators are inside,” she said. “You and your team will accompany me.”
“No, for the striking miners.”
“I have given your request the thought it deserves.” “Kill them.”
"I was concerned about you, FN-2003,” she said. “I am glad you’ve proven me wrong.”
“You’re now stormtroopers,” she said. “You’re now one of us.”
Poe Dameron #2
I do not understand why you keep these... people, Agent Terex.
The First Order is not the Empire. We are pure. We have been through the crucible and emerged stronger.
This is about a man named Poe Dameron. He is -
Your sources are good.
Dameron recently led a mission that intercepted key information being passed to us by a New Republic senator. We need to know what he got and what the Resistance intends to do with it.
You've been assigned significant resources to complete this mission.
The true offensive will begin soon... But only if there are no loose ends.
Where did you hear that term?
Poe Dameron must be found, and we need the information he stole. That is your mission, Agent Terex. Do not fail.
Yes, Terex. Every officer in the First Order knows exactly where you came from. That is why we say it.
Do not fail, Terex. Find Poe Dameron.
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