It was directed by Paul Henreid from a screenplay by Oscar Millard and Albert Beich, from the story La Otra by Rian James, previously filmed in a Mexican version starring Dolores del Río.

It started when Margaret faked a pregnancy to "steal" Edith's fiancé, Francesco "Frank" DeLorca, a rich American military officer both sisters dated during World War II.

Meanwhile, Jim, a police detective who had been seeing Edith steadily before her "suicide", visits the fake Margaret several times, asking questions.

Edith's scheme runs into trouble when Margaret's lover, Tony, unexpectedly shows up and quickly sees through her charade.

Already suspicious about DeLorca's death, Jim leads a police investigation, exhuming Frank's body and later finding traces of arsenic.

The plot of Dead Ringer was the same as that of the 1946 Mexican film, La Otra, directed by Roberto Gavaldón and starring Dolores del Río.

The jazz combo in Edie's Bar was composed of electronic organist Perry Lee Blackwell and drummer Kenny Dennis, both noted musicians, but uncredited in the film.

Makeup artist Gene Hibbs was hired due to his unique talent for making older actresses look younger through a "painting" technique.

[3] The film was directed by the actor Paul Henreid, Davis's co-star in the 1942 romantic drama Now, Voyager.