February 29 2024

CSI Files

An archive of CSI, NCIS, Criminal Minds and crime drama news

Assume Nothing

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Series: 'CSI: Crime Scene Investigation'
Episode Title: 'Assume Nothing'
Episode Number: 0401
Synopsis: "In Part 1 of the two-part fourth-season opener, a woman is found murdered in a casino hotel room with her throat slit and her husband also turns up dead in his car. The investigation is compromised by Nick when he makes an error in judgment. There is also a surprising development in the Sam Braun case that leaves Catherine worried."

Original Airdate: September 25, 2003
Rerun: November 16, 2003
Fan Rating: 8.4/10 (Full Poll Results)
Nielsens Rating: 17.2/26 (Full Report)


Written By: Anthony E. Zuiker & Danny Cannon
Directed By: Richard J. Lewis

Guest Stars:


  • Rumoured to be the first part of a two-part story about a pair of husband-and-wife serial killers. (July 17, 2003 - CSI Files)

  • Executive producer Carol Mendelsohn: "One of the biggest surprises of the new season will be in the first episode. There's a reason that that episode is entitled 'Assume Nothing.' All I can say is no one should leave their La-Z-Boy [recliner] during the last five minutes." (July 21, 2003 - CSI Files)

  • The premiere will reportedly wrap up Gil Grissom's hearing storyline. (July 29, 2003 - CSI Files)

  • Filmed location scenes in two-day shoot at the Green Valley Ranch, Las Vegas. (August 12, 2003 - CSI Files)

  • Gil Grissom's hearing will be restored as the result of the operation he went through at the end of last season. "He hears better, we find that out right off the bat," said actor William Petersen. (September 05, 2003 - CSI Files)

  • Premiered at a special screening at the Museum of Television and Radio in Los Angeles on September 15. (September 17, 2003 - CSI Files)

Poll Results

How would you rate 'Assume Nothing'?
9-10 48.8% - (149 Votes)
7-8 23.6% - (72 Votes)
Wasn't able to see it 17.7% - (54 Votes)
5-6 5.5% - (17 Votes)
3-4 1.6% - (5 Votes)
1-2 1.6% - (5 Votes)
Didn't want to see it 0.9% - (3 Votes)

Total Votes: 305


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Next: 'All For Our Country'
Return: 'CSI: Crime Scene Investigation' Episode Guide

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