Will's "message-in-a-bottle" experiments deplete the supply of fuel for the Jupiter 2. John and Don work on an alternate fuel source, but they cannot stabilize the output. Deciding to build a smaller, 2-man craft, they pull the reactor chamber out and use Will's experiments to construct a "space raft."
Stars: Guy Williams, June Lockhart, Mark Goddard
Director(s): Sobey Martin
Writer(s): Peter Packer, Irwin Allen