Sean Penn and Netflix are fighting over a documentary series that will become available early Friday, with a lawyer for Mr. Penn saying in a letter to the streaming service that it is “hereby on notice that blood will be on their hands if this film causes bodily harm.”

The series in question, “The Day I Met El Chapo: The Kate del Castillo Story,” centers on the bizarre episode in October 2015 when Ms. del Castillo, a Mexican actress, and Mr. Penn were given an audience with one of the world’s most wanted men, the drug dealer Joaquín Guzmán Loera, also known as El Chapo.

Mr. Penn later wrote about the meeting in an article for Rolling Stone that was published just a day after Mr. Guzmán was captured by authorities.

In a letter sent last week, Mr. Penn’s lawyer, Theodore J. Boutrous Jr., warned Netflix that the series would put his client in danger and demanded that the company make changes to the content of the documentary. Mr. Penn did not participate in “The Day I Met El Chapo,” and it largely revolves around Ms. del Castillo’s account. The documentary has not been changed.