The second his illusion vanished from Loki's cell, Lucius opened the door.
It was a small courtesy.
Loki would be out in a matter of minutes anyway once the rest of his plan unfolded, so there was no reason to be stingy with goodwill. It cost Lucius nothing. He had always believed that if one was going to build a future relationship with a fellow menace, then one ought to start with practical politeness rather than sentimental drivel.
The lock disengaged with a soft mechanical click.
Lucius left it there and moved off at an easy pace, still invisible, still entirely at home in somebody else's flying fortress.
He took the scenic way up because he could.
The Helicarrier remained a magnificent piece of engineering. Warning lights shifted from standby calm to active irritation along the corridor edges. Crew ran past with the clipped panic of people trained well enough to keep moving but not well enough to hide that the situation had already slipped outside normal parameters.
Lucius looked around with genuine pleasure.
Seeing the Helicarrier in motion from inside it was worth the trip alone. Phastos's gift still itched at the back of his mind with improvements. Better redundancy here. Smarter load distribution there. Less foolish reliance on the same self-important command nodes everywhere. Humans really did love building temples to control and then acting shocked when control became a choke point.
The explosion hit while he was still climbing to the upper levels.
It came in two parts.
First, the impact travelled through the ship like a bad idea had just been forced into the engine housing with a hammer. Then the sound, a brutal concussion through metal, air, and structure that shoved alarms alive in every direction at once.
The whole carrier lurched.
Lucius planted one foot, rode the motion easily, and dropped his invisibility with a pleasant smile on his face.
The fun had begun.
Red light strobed along the corridor, and klaxons screamed. Somewhere above him, people were already shouting over comms, every voice insisting it had control of a situation that had clearly slipped the leash.
The security systems noticed him immediately.
Identification grids flickered across the corridor monitors. Access denial warnings flashed. A sharp secondary alarm rose and tagged him as an unauthorised presence the moment the cameras reacquired his now entirely visible and handsome self. It would have been more flattering under calmer circumstances.
Instead, the security breach notice was swallowed beneath the other system warnings pouring in from the damaged engine, decompression checks, power strain, containment breaches, lift failures, and the delicious administrative shrieking that followed the realisation that when you take the flying out of a flying fortress, what remains is a falling one.
Lucius watched the chaos around him and chuckled.
He kept walking.
By the time he reached the upper levels, Tony Stark was already running towards his armour station in a dark shirt, no helmet or suit, just speed and irritation and the ugly clarity of a man who knew his day had finally reached its natural conclusion.
Tony saw him first and nearly slowed from pure disbelief.
"Lucius." Relief cut straight through the annoyance in his tone. "The man I was looking for."
Lucius stopped with leisurely dignity and gave him the sort of smile kings probably reserved for jesters who had accidentally said something useful.
"Go on, praise me more. Feel free to add descriptions, such as heroic, devastatingly handsome, or indispensable in a crisis. I don't mind accuracy."
Tony would, under normal conditions, have answered with something properly insulting.
Under normal conditions, however, he would not have been sprinting towards battle while desperately wishing the smug fruit monster in front of him might be convinced to lay the absurd, strange shield over his suit again. The expo had left a lasting educational mark on his sense of priorities.
So he bit back the first three replies and kept moving.
Lucius turned towards him with a wounded expression so shameless it deserved applause.
"How long has it been since we last met? And this is the greeting I get?" He pressed the back of one hand to his forehead. "Not even gratitude for rescuing you from your own homicidal robots. Not even an apology for those devastating punches you landed on my perfect face. Do you have any idea what those punches did to my facial harmony? Not even remorse over the slanderous accusation of car theft."
Tony jabbed a finger at him while still walking.
"I already gave you a collection of supercars, you bloodsucker."
Lucius gasped.
"I can't believe my best friend is such an evil character. So evil that after all the good I have done for him, he has not even thought to compensate me further. No fresh motors. No emotional support vehicles. No gesture of repentance."
Tony hit the armour platform and turned on him fully.
"I'll add more if you help me."
Lucius dropped the wounded act at once. That was the sort of sentence he had been waiting for.
"Excellent."
He reached out with telepathy and pushed the images directly into Tony's head before the man could do anything as defensive as thinking clearly. Four sleek silhouettes flashed across Tony's mind in merciless detail, two Koenigseggs and two Bugattis, each one finished in colours Lucius had selected with the malicious eye of a man who wanted his theft to look expensive even before delivery.
Tony stopped dead.
Then he exploded.
"No. Absolutely not. I am not buying you two Koenigseggs and two Bugattis, you thug. Choose something else."
Lucius shrugged with serene disappointment.
"Of course. In that case, a very simple superyacht will do."
Tony stared.
Lucius continued as though discussing salad dressing.
"I'll send the details to JARVIS later."
Then he lifted one hand and let the shield settle around Tony's body with a soft shimmering ripple, a second skin of unseen reinforcement settling into place around the metal before the suit had even finished assembling.
Tony's eyes twitched as the repulsor rig locked across his arms.
"You are the worst person I know."
Lucius considered that and decided it was intended as admiration.
"Enjoy the armour. If you need rescue, simply shout 'My knight in shining armour', and I shall arrive on a unicorn that shoots rainbows out it's arse to save you."
Tony stepped into the rest of the suit with murderous speed and shot him a glare that would have been more effective if the gratitude underneath it were not leaking through in visible flashes.
"I wish I had a gun on me."
Lucius looked him over and smiled.
"My dear Tony, with your judgment under pressure, I rather think that would only improve my odds."
The faceplate snapped shut before Tony said something he would later have to admit was emotionally revealing.
Lucius stepped aside with magnanimity and watched the suit seal.
This, more than the heroics, was why he liked Tony. The man understood transactions, vanity, improvisation, and the importance of building things that could physically punch a bad day until it behaved.
As Iron Man shot away down the corridor towards the breach, Lucius resumed his own leisurely walk in the direction of the bridge.
He wondered what his old acquaintance Maria Hill was doing lately.
Hiding, ideally.
That would at least suggest she had learnt something from the educational process.
He passed two agents dragging emergency equipment towards a sealed bulkhead and noticed immediately that neither mind matched the face it wore.
Skrulls.
More than one.
Lucius slowed for half a heartbeat, enough to give them a second look without making it obvious. The green little infiltration enthusiasts were riding around in SHIELD skins as if the place had not already collected enough bad habits without importing a fresh species for the paperwork.
He scoffed under his breath.
"Fury really does know who to trust."
He kept walking.
Around him, the Helicarrier convulsed through the next phase of crisis. Agents ran. Doors slammed shut on automatic cycles. Emergency shutters descended in sections where the pressure loss readings spiked too high. On internal comms, voices tripped over each other trying to impose order on physics. The ship had ceased being a command centre and had become what all expensive institutions became when wounded.
A machine for revealing priorities.
Tony's was the engine.
Fury's would be the bridge.
Banner's would shortly become everyone's problem, but mostly Thor and Romanoff's.
And Hill would be somewhere around the bridge of this flying steel safehouse SHIELD had mistaken for protection.
He smiled at the thought and turned the next corner without hurrying in the slightest.
After all, good reunions should not be rushed.