"Negative. It's not Dad's."

The resulting widespread aura of disappointment was almost audible across the International Rescue comm channel.

After a moment's silence for what could have been - nah, we were probably kidding ourselves anyway. Anyway, Virgil swiftly attempted to drag their aquanaut back on task. "Sorry, Gordon. Now let's get back to work. I'm having a little trouble grabbing hold of the station."

"Not so fast, Virgil." Gordon had been captivated by the glowing object sharing the fault trench with his submarine. "Whatever it is I'm looking at, it shouldn't be here...!"

The object soon added fuel to that theory by glowing in a much harsher fashion. At the same time, Gordon felt rather than heard a distinct rumbling in the water. "Uh oh! ...John, it's a seaquake!"

John, in Thunderbird Five, had come to the same conclusion. "Thunderbird Four, get out of there!"

"Oh, no. John! Thunderbird Five!-ungh."

A little yellow submarine lay at the bottom of the fault trench under a fallen rock. Its lights were off and nobody was home.

"Gordon, come in. Thunderbird Four, can you read me? Gordon!"

"International Rescue, we're having another seaquake! ...We've just lost half the legs!"

The research lab, robbed of support on one side, was now tilting dangerously towards the chasm it was meant to be researching. Thunderbird One, now supporting a significant portion of the lab's weight, strained under the added load.

"Increasing thrust to compensate." Scott looked nearly as stressed as he felt. "You need to get a grip on this thing fast, Thunderbird Two, or I'm going under."

Fortunately, Thunderbird Two chose that moment to cooperate, finally latching onto the lab and pulling it upright to Virgil's triumphant call of "Okay, I've got it!" As the lab's three crew steadied themselves on whatever they could, the pilots above shared a sigh of relief. "As long as we keep it stable, it should hold out long enough for Gordon to do the evac."

"FAB. I just hope John can get in contact with him soon."

But the minutes dragged on, and the quakes kept coming, and John couldn't.

"Still nothing from Gordon. I'm worried about him."

"Virgil, if you have a plan B, make it quick. I'm not sure how much longer we can hold on."

"I'm not sure either, and since when did we have a plan B?"

"International Rescue, the control room is flooding. Just - get us out of here!"

(At this point on the island, Alan and Kayo finally got back from orbit, the former complaining that "We leave the planet for a few hours and the whole world falls apart!" and the latter reminding him that "At least it has TV.")

After an interminable wait, Scott decided the situation was as bad as it could be allowed to get. "Okay, we can't wait any longer for Gordon. Thunderbird Five, have the crew prepare for immediate evac. Are there any other ways they could get out?"

"This is Thunderbird Five. I have the lab's floorplan. There's an emergency hatch, ventral starboard midships - if they can operate it."

"No good. We've tried it already; it's jammed," the station commander pitched in.

"I don't see any other way built in." John examined his scan some more. "The breach letting the water in - where is it?"

"Sublevel six, right on the bottom."

"All right. It's big enough for you to escape - can you get there?"

"There's too much current right now. If the water stops flooding in through it, we might make it."

"Right." John considered their options. "As strange as it may seem, the best way to stop the current is to flood the entire lab as fast as possible. Sealab crew, seal any sections that aren't flooded, and open all hatches to sections that are still flooding - you need to fill every breached section to stop the current."

"And you need to do it fast," Scott added. "We can't hold this thing up forever."

"Thunderbird Five to Thunderbirds One and Two. The lab is filling up faster - the crew must be making progress."

"International Rescue, we've opened everything we can. We'll swim out as soon as the current stops. I'm hoping it's soon."

"So am I. That lab is seriously heavy." Virgil considered his position. Thunderbird Two had been hovering under great strain for the past twenty minutes, holding an undersea research lab up and stopping it from taking a fall which would certainly kill its crew. Thunderbird One was theoretically assisting, but looked in worse shape itself, being pulled much closer to the water. And - oh dear.

"Thunderbird Five, detecting another seaquake."

"I can confirm that!"

Both airborne Thunderbirds strained to keep the lab upright as the seafloor betrayed it yet again. It was at this least opportune time that the lab started transmitting again. "It isn't looking good in here! Isn't there anything you can do?!"

"I'm afraid not. It's all we can do to stop - ugh," Virgil's craft bucked again as the quake spiked, "stop the lab falling as it is."

"The shock's breached another section," Thunderbird Five reported far too calmly. "You're in for another couple of minutes."

"Better be fast minutes," Scott muttered. "I'm not exactly flying a submarine here."

"International Rescue, the current's stopped. We're swimming out now."

"Understood. I'll guide you out. Turn right at the end of this passageway..."

As John's directions faded into the background, Scott sighed - he'd gotten out of this without the paint on his 'bird getting wet.

Naturally, the universe punished this premature assumption by yanking it down again.

"Ugh! The lab is shifting... it's going to flip any second!"

"Thunderbird Five to lab crew. If you're going to get out, now would be a good time!"

Another lurch. Thunderbird One thudded into the ocean surface, spraying the interior with saltwater.

"The lab's too heavy!" Virgil was in an unchacteristic panic by now. "It's pulling us both under!"

Another lurch. "Thunderbird One to Thunderbird Two, I have to disengage or take a bath!"

"Thunderbird Five to lab crew, what's your status?"

Another lurch. Thunderbird One peeled off, unable to sink any lower. Thunderbird Two strained under the added load.

"Thunderbird Five to lab crew, come in please."

Another lurch, and the lab toppled over the edge. Thunderbird Two began an inexorable descent -

"Thunderbird Five to lab crew, can you hear me?"

- until one of its clamps ripped the composite sheet it was attached to off the station body. The other promptly followed, and the lab fell to its doom.

Now notably higher above the ocean, Virgil took a moment to collect himself. As he did, Scott was adding his voice to the inquisition. "Lab crew, this is International Rescue. Do you read me?"

The silence stretched far too long, until - "I... The, ah, two of us are okay."

"I thought there were three."

"The commander didn't make it out. He was going to be last out the hole. Knocked his head when the lab dropped, and it took him with it."

All involved shared a moment's silence.

"Could you pick us up?"

"Certainly. Thunderbird Two's recovery module is waiting almost directly above you - just swim up."

"Gladly."

With the mission complete - mostly, anyway - John turned his attention to other matters. "Scott, Virgil, I still can't find Gordon. We're going to have to come back for him later."

"Are you seriously -" "John, we can't just -"

"Guys. Gordon will be fine. He'll find a way to get in touch."

Thunderbirds One and Two reluctantly departed for home base.

Thunderbird Five's occupant moved for the space elevator. He'd never actually lost track of their aquanaut. It was just that every diagnostic he'd run had told him that the [lack of] heartbeat had been accurate for at least thirty minutes.

Non-canon bonus section!

"This is rather alarming. There's a note here, addressed to International Rescue. It says, 'Press me, and all your questions will be answered'...?"

Lady Penelope's find in the warehouse was met with skepticism.

"I say we press the button and deal with the consequences." Scott, usually not the impulsive one, seemed to be making an exception.

Alan decided it was time for Genre Savvy. "I smell a trap."

(Grandma noted that "I wouldn't touch that with a ten-foot pole.")

"I want answers."

"I'm telling you, trap."

John, substitute voice of reason in Scott's absence, decided that the oldest-youngest bickering was getting them nowhere. "Kayo, what do you think?"

"It definitely looks dodgy, but... what's the worst that could happen?"

In the warehouse, Parker apparently shared her opinion. With a remark to that effect, he reached for the button.

"Parker-!"

He pressed the button.

KABOOM