Lost in Space are to be cryogenically frozen for the voyage, and they are set to be unfrozen when the spacecraft approaches its destination. Meanwhile, Dr. Zachary Smith (Jonathan Harris), Alpha Control's doctor, is revealed to be a saboteur on behalf of an unnamed nation. After disposing of a guard who catches him on board the spacecraft, Smith reprograms the "Jupiter 2"s B-9 environmental control robot (voiced by Dick Tufeld) to destroy critical systems on the spaceship eight hours after launch. Smith, however, becomes trapped aboard at launch and his extra weight throws the "Jupiter 2" off course, causing it to encounter a
Lost in Space direction for the fourth season with CBS chief executive Bill Paley, Allen was furious when told that the budget would be cut by 15% from Season Three. The "Lost in Space Forever" DVD cites declining ratings and escalating costs as the reasons for cancellation. Irwin Allen admitted that the Season 3 ratings showed an increasing percentage of children among the total viewers, meaning a drop in the "quality audience" that advertisers preferred. Guy Williams grew embittered with his role on the show as it became increasingly "campy" in Seasons 2 and 3 while centering squarely on the antics of Harris'