They took the Enterprise out on a Thursday, out of spacedock, at 0340, during a refit.
It was, Scotty said afterward, the easiest thing he had ever done, and he said it with an expression that made everybody look away, because what he meant was that it had been easy, and that this was the part that would keep him awake.
The ship was in dock for a nacelle overhaul. Skeleton crew, forty-one aboard instead of four hundred and thirty. Pike was planetside at a strategic conference and not due back for nine days. The dock's own controllers had authority over her moorings and would have caught it in under ninety seconds.
Except that the dock's controllers took their traffic authorizations over a subspace channel. And the woman monitoring that channel had spent twenty-six months learning to make a channel say exactly what she wanted and nothing else.
"Yard control confirms departure window," said Uhura, in a voice of complete calm, into a comm circuit she had invented eleven days earlier and which did not exist. "Enterprise cleared for spacedock egress under Priority Two, Admiral's discretion. Code follows."
The code followed. That was the thing that had taken her eleven days. It was not a forgery. It was a valid Priority Two authorization, generated by the actual Starfleet cryptographic system, using an actual admiral's actual key, and the reason she had it was that in 2266 a communications officer had spent a very boring week in a very boring relay station on Deneva writing down, for no reason at all, the precise sequence of handshakes by which flag authorizations were issued, because she had been bored and wanted to see how it worked.
She had kept the notes for three years, out of pure professional magpie instinct, and dug them out on the second night after Spock said the words, and built a key out of them.
"Yard control acknowledges," said yard control.
"Moorings released," said the dock.
"Ye're a terrifying woman, lass," said Montgomery Scott.
"Yes, sir," said Nyota Uhura.
* * *
They were three light years out before anybody in the Federation knew the ship was gone.
By then Scotty had done something to the warp core that Starfleet would spend eight months failing to reproduce and eventually classify, and the Enterprise was making warp eight point six with forty-one aboard and no captain and a quarantine buoy nine days ahead of her.
Spock stood at the science station and did not sit in the center seat. Nobody remarked on it. He gave orders from his own station for the first eleven hours of an unsanctioned voyage, and the four other people who understood exactly why did not say a word.
At 0400 on the fourth day the intercom whistled.
"Bridge to Mister Spock."
"Spock here."
"Sir," said Lieutenant Galloway, "you had better come up."