For the MST3K episode, see MST3K K09 - Phase IV.

Phase IV is a 1974 horror movie.


A colony of ants develops a collective intelligence and begins to terrorize the local populace in a secluded desert region of Arizona.


  • Michael Murphy as James R. Lesko
  • Nigel Davenport as Dr. Ernest D. Hubbs
  • Lynne Frederick as Kendra Eldridge
  • Alan Gifford as Mr. Eldridge


  • A novelization by Barry N. Malzberg was released. Based on an earlier draft of the script, the novel has a different ending than the film.

MST3K Connections[]

Critical Response[]

  • Leonard Maltin wrote: "Two-and-a-half stars ... Visually stunning but rather incomprehensible science fiction about colony of super-intelligent ants (normal-sized, for a change) running rampant at a lonely scientific outpost. Difficult, but not without its rewards. Alternate final reel was discovered in Bass’ archives and first shown in 2012."[1]


  1. Leonard Maltin's Movie Guide, 2015 Edition