While the film carries the same title as the 1969 book "Thirteen Days" by former Attorney General Robert F. Kennedy, it is in fact based on the 1997 book, "The Kennedy Tapes: Inside the White House During the Cuban Missile Crisis", by Ernest R. May and Philip D. Zelikow. It is the second docudrama made about the crisis, the first being 1974's "The Missiles of October", which was based on Kennedy's book. The 2000 film contains some newly declassified information not available to the earlier production, but takes greater dramatic license, particularly in its choice of O'Donnell as protagonist. It received generally positive reviews from critics who praised the screenplay and performances of the cast but was a box office bomb grossing $66.6 million against its $80 million budget.