BEN 10: ULTIMATE ALIEN
"Chain Reaction"
A Fan-Made Episode Script (Original Story)
COLD OPEN
EXT. BELLWOOD FREIGHT YARD — NIGHT
Rows of cargo containers stacked in towering grids, sodium lights buzzing overhead. A freight train idles on a side track, engine running, no crew in sight. One container's door hangs open, swinging slightly, empty.
MAX TENNYSON walks the yard with a Plumber scanner, BEN, GWEN, and KEVIN close behind.
MAX
(reading the scanner)
Three containers reported missing cargo over the past two nights. No broken locks, no cut fences. Just... gone.
GWEN
(scanning the open container)
This one wasn't pried open. The locking mechanism's still intact — whatever took the cargo went through the wall.
She gestures to a clean, perfectly circular hole punched through the container's steel siding, edges melted smooth.
KEVIN
(whistling low)
That's not a crowbar job.
A distant METALLIC CLANG echoes from deeper in the yard — rhythmic, deliberate, like something heavy moving with purpose between the container stacks.
BEN
(already moving toward the sound)
Let's go find out what's doing the moving.
ACT ONE
EXT. FREIGHT YARD — CONTAINER MAZE — CONTINUOUS
Narrow corridors between towering stacks. The clanging grows louder, closer, accompanied now by a low mechanical WHIR. Ben slaps the Ultimatrix.
[TRANSFORMATION SEQUENCE]
Green light wraps him. His body lengthens, joints reshaping into something built purely for speed — sleek, armored, low-slung, wheels spinning into place at his heels.
BEN (AS FASTTRACK)
(grinning, voice quick and clipped)
Fasttrack! Alright, let's see what's fast enough to be making that much noise.
He rockets down the corridor between container stacks, weaving tight corners at speed, and rounds a final turn to find the source: a hulking, segmented machine, vaguely insectoid, dragging a stolen container behind it on six mechanical legs, cargo crate clutched in a claw-like forelimb.
FASTTRACK
(skidding to a stop)
Okay. Definitely didn't expect a robot bug doing furniture delivery.
The machine's sensors swivel toward him, claws tightening on the stolen crate. It doesn't flee — instead, panels along its back hiss open, revealing weapon ports charging with a dull orange glow.
FASTTRACK (CONT'D)
(backing up fast)
Yeah, that's a "we're fighting now" kind of glow.
The machine fires a spread of concussive blasts. Fasttrack weaves between them at full speed, using his agility to dodge through the narrow gaps between container stacks, but the machine pivots with unsettling precision, tracking him far better than something built like scrap metal should.
FASTTRACK
(over comm, fast)
Whatever this thing is, it's not dumb. It's adjusting to my speed in real time.
GWEN (V.O.)
(urgent)
Then don't out-speed it. Out-muscle it. Speed's not gonna matter if you can't actually stop it from running.
Fasttrack ducks behind a container stack, breathing hard, glancing at the Ultimatrix.
FASTTRACK
(determined)
Fair point.
ACT TWO
[TRANSFORMATION SEQUENCE]
Green light wraps him again. His frame doubles in width, two extra arms sprouting from his sides, skin reddening, muscles bulking dramatically.
BEN (AS FOUR ARMS)
(booming, flexing all four fists)
Four Arms! Now we're talking.
He bursts from cover and CHARGES the machine head-on, catching its first swing on two raised forearms and using the other two fists to slam a haymaker into its segmented torso, sending it skidding back several yards, crate clattering from its grip.
FOUR ARMS
(grinning)
There we go! Speed's nice, but sometimes you just gotta hit something really, really hard.
The machine recovers fast, claws snapping forward, and Four Arms grapples it directly, all four hands locking around its forelimbs in a brute test of strength.
Gwen and Kevin arrive on the scene, Kevin already absorbing nearby scrap metal for armor.
KEVIN
(eyeing the machine)
That's a lot of moving parts for something that's apparently just stealing cargo.
GWEN
(scanning quickly)
It's not random cargo, either — I'm reading trace energy signatures on the crates it's already taken. Components. Power cells, conductive alloys, precision parts.
KEVIN
So it's not robbing a freight yard. It's shopping.
GWEN
(grim)
Building something. And every part we let it keep makes that something more complete.
The machine, straining against Four Arms' grip, suddenly vents a burst of pressurized gas from its joints, momentarily disorienting him long enough to wrench free and bolt down the corridor, dragging a second crate it had stashed nearby.
FOUR ARMS
(coughing, waving off the gas)
Okay — it's not just strong, it's resourceful. Great.
EXT. FREIGHT YARD — MAIN RAIL LINE — MOMENTS LATER
The fleeing machine barrels toward the idling freight train, clearly intending to use it as either cover or transport. Four Arms gives chase but the machine's lead is widening, scrambling up the side of a container car with surprising agility for its bulk.
FOUR ARMS
(grunting, falling behind)
Yeah, four arms doesn't help much with "climbing things fast."
He glances at the Ultimatrix, already flickering.
FOUR ARMS (CONT'D)
Time for plan C.
[TRANSFORMATION SEQUENCE]
Green light. His already-bulky frame compacts and rounds out, limbs drawing inward, a thick segmented shell forming across his back as he drops into a low, rolling crouch.
BEN (AS CANNONBOLT)
(voice echoing slightly inside his shell)
Cannonbolt! Alright. Let's roll with this one. Literally.
He curls into a ball and launches himself in a tight, accelerating spin, rocketing up the side of the container car in a tight spiral and slamming directly into the fleeing machine, sending it tumbling off the train car entirely.
CANNONBOLT
(uncurling, satisfied)
Yeah. That's more like it.
ACT THREE
The machine crashes to the gravel below, dented but functional, scrambling upright with claws already grabbing for the dropped crate. Cannonbolt drops down to block its path, Gwen and Kevin catching up at ground level.
GWEN
(scanning urgently)
Ben, that machine's core energy signature just spiked. I think it's done collecting — it's about to use everything it's gathered.
Right on cue, the machine's back panels split wide open, revealing a half-assembled secondary structure within its own chassis — clearly building a larger, more dangerous war-form out of every stolen component, faster than expected, clearly accelerating now that it senses it's cornered.
KEVIN
(backing up)
Oh, that's not great.
CANNONBOLT
(grim, watching it bulk up before their eyes)
No more chasing it down piece by piece. Time to actually finish this.
He glances at the Ultimatrix symbol, flickering rapidly now.
CANNONBOLT (CONT'D)
Let's see what the heavy-duty version can do.
[ULTIMATE TRANSFORMATION SEQUENCE]
The symbol on Cannonbolt's chest SNAPS open, deploying mechanical petals across his already-armored frame. His shell thickens further, spikes erupting along his curled form, plating brightening with energy conduits, his rolling spin now trailing a visible arc of crackling power.
BEN (AS ULTIMATE CANNONBOLT)
(booming, echoing)
Ultimate Cannonbolt!
The half-finished war-machine, sensing the new threat, fires everything it has — a barrage of blasts and claw-strikes. Ultimate Cannonbolt curls instantly into his rolling form, spiked shell absorbing and deflecting every hit without slowing his charge.
ULTIMATE CANNONBOLT
(muffled, from within his spin)
Thanks for the running start!
He slams into the machine at full, spike-enhanced velocity, the impact alone crumpling its half-built secondary chassis on contact. He uncurls mid-collision, driving both spiked forearms directly into the machine's exposed core with controlled, decisive force — not wild destruction, but a precise shutdown strike.
The machine SHUDDERS violently, all its stolen components powering down in sequence, panels sealing shut, the half-finished war-form collapsing into harmless, inert wreckage scattered across the rail line.
Silence, except for settling gravel and distant train-yard hums.
ULTIMATE CANNONBOLT
(standing, brushing off gravel)
There. Heavy-duty mode: officially worth the upgrade.
KEVIN
(impressed despite himself)
Okay, I'll admit, going Fasttrack-then-Four-Arms-then-Cannonbolt-then-Ultimate-Cannonbolt in one night is a flex.
GWEN
(checking her scanner on the wreckage)
In fairness, it kept adapting. He kind of had to.
TAG SCENE
EXT. FREIGHT YARD — LATER
Dawn light. Plumber crews load the deactivated machine's remains onto a containment truck. Max examines a recovered component, frowning thoughtfully. Ben, back to human, sits on a stack of pallets with Gwen and Kevin.
MAX
(holding up the component)
Salvage-class construction drone. Old tech, but resourceful — designed to scavenge materials and self-assemble into something bigger when it senses a deadline or a threat. We've seen scattered reports of these for years. Never recovered one intact before.
GWEN
Any idea who built it? Or why it ended up in our freight yard specifically?
MAX
(grim)
Not yet. But "old tech showing up out of nowhere, building toward something bigger" isn't exactly a comforting pattern.
BEN
(stretching, exhausted)
Add it to the list.
KEVIN
(climbing into his car)
That list is doing numbers lately.
Max gives a small nod before heading off to oversee the rest of cleanup. Gwen glances at Ben.
GWEN
Three aliens and an Ultimate form in one night. New record?
BEN
(smirking, glancing at the Ultimatrix — calm, green, ordinary now)
Pretty sure I've topped this before. But it's definitely up there.
He climbs in after Kevin. Gwen shakes her head, smiling, and follows as the freight yard slowly returns to its quiet, ordinary hum behind them.
FADE OUT.
END OF EPISODE