All player characters were rolled up using High Guard Imperial Navy, or Mercenary for Imperial Marines. All were still active service, so any number of years could be used (instead of just groups of 4) , and no one was higher than Lieutenant Commander. The players were all assigned to to be part of the Frozen Watch aboard the AHL class cruiser Haunting Thunder.
The adventure began with the players being thawed out and informed by a ensign they were now the command crew of the ship. Severly damaged by a Zhodani attack (Fourth Frontier War) the ship had mis-jumped deep into Zhodani territory. The spinal mount was destroyed, most of the crew dead and fighters gone. Three type-S Scouts had been carried attached to the hull during this patrol and were still with them.
I had pictured this campaign as being Get The Boys Back Home, limping a crippled cruiser back through Zhodani lines to get home. Jon, our new ship's captain, saw the adventure differently. At Jump 5, the Haunting Thunder was as fast as the fastest couriers in the Consulate. First, they violated restrictions and visited a Red Zone populated by humanoids at TL8, and after accidentally triggering a nuclear war between rival superpowers, they recruited locals to fill their crew and set course for the Zhodani Capital. Patrol ships and planetary defence boats they encountered couldn't really hurt them by High Guard Rules, and this was also back before MegaTraveller explained sensors better, so the stealth from the Black Globe was pictured like the Romulan's Cloaking device from Star Trek.
You know, a ship with a black globe far from where any warship should be can get quite far, especially with a pile of Particle Accelerators and a few nuclear missiles to use against merchant ships and other unfortunates who ran into the Haunting Thunder. At one point some crew mutinied, but Captain Jon took control of the ship's grav and played with the On-Off button until thing cooled down. He almost got into a sword duel with the leader of the mutiny, but an Aslan Marine threw the guy down the power plant shaft just before swords were drawn. The campaign finally ended because they were developing plans to ram the Zhodani homeworld at about 0.8 the speed of light, with Black Globe on, and then in unrelated events some players stopped talking to each other, and one went off to California.