I feel like a stowaway on someone's honeymoon.

Suspecting it was a stowaway from one of the boxes, she took the broom upstairs, where most of the boxes were.

Karen and Frosty stowaway on a refrigerated train car.

Working doors and a rear stowaway area give this vehicle a realistic look as well.

The premise was simple, and maybe even overly simplistic - a space vehicle carrying a family (the Robinsons) that were going to start a space colony 'in Alpha Centauri' was sabotaged by the stowaway Dr. Smith, and thrown off course.