Disclaimer: I don't own Stargate: SG-1.
Author's note: This story shows what the alternate Colonel Mitchell was talking about when he told the regular Colonel Mitchell to cut the green one in the episode 'Ripple Effect'.
When the time comes...
Colonel Cameron Mitchell is in the engine-room of an alien ship on the way toward Earth. The ship is an automated vessel equipped with a weapon that could destroy Earth with only one shot.
"There's gotta be a way to disarm the weapon..." says Colonel Mitchell to himself.
He pull off a piece of the wall to reveal an alien panel.
There's a lot of controls, wires and buttons.
"Shit! I don't understand a thing about this!" says Colonel Mitchell.
Suddenly he remember something that happened years earlier in 2006.
Flashback to SGC gate-room 2006.
A Colonel Cameron Mitchell from an alternate universe wearing a black uniform is about to step through the Stargate when he turn around and look at the Colonel Mitchell from the regular universe and says "Hey, Mitchell...! When the time comes, cut the green one!"
Up in the control-room the regular Colonel Mitchell looks at Daniel Jackson next to him. "Jackson, what was that about?"
"I'm sure you'll find out one day." says Daniel.
Present time.
"This has to be what the other me was talkin' about before he left...!" says Colonel Mitchell.
Colonel Mitchell pull out his pocket-knife and cut off the only green wire that he can find.
A red light is being shut off.
"Yes, the other me was right!" says Colonel Mitchell when he understands that the weapon is offline.
Half an hour later when the ship enter Earth's solar-system an Asgard transporter beam pull Colonel Mitchell off the alien ship as it self-destructs.
Colonel Mitchell re-appear on the bridge of the battleship Herakles III.
"How did you do it, Cam?" says General Samantha Carter.
"Remember what the other Mitchell said in 2006 before he went back to his own reality?" says Colonel Mitchell.
"Yeah! He told you that when the time comes, you should cut the green one." says General Carter.
"Exactly! That is what I did!" says Colonel Mitchell.
"I guess the other Colonel Cameron Mitchell was right then..."
"Yeah, Sam, he was."
The End.
