Marian Price is taking legal action against Disney+ after she was depicted killing Jean McConville in one of its new series.
The series, Say Nothing, portrays the murder and secret burial of Ms McConville by the IRA in 1972.
She is known as one of the Disappeared, a group of 17 people who were abducted, killed and secretly buried by republican paramilitaries during the Troubles.
Her remains were finally found in 2003 at Shelling Hill Beach in Co Louth by the Independent Commission for the Location of Victims' Remains.
No-one has ever been prosecuted over her death, which left her ten children orphaned.
The dramatised series, which is published by Disney on its streaming service Disney+, is premised upon the 2018 book of the same name, published by Patrick Radden Keefe.
Ms Price, who is also known as Marian McGlinchey, has initiated formal legal proceedings against Disney.
In a statement, Peter Corrigan, a solicitor for Phoenix Law, said: "The publication in question depicts our client, Marian Price, as the person to whom was responsible for murdering Ms Jean McConville. Mrs Price has initiated legal proceedings as a result."
"Given the context, it is difficult to envisage a more egregious allegation than the one to which has been levelled against our client.
"As someone who has been involved at every level of the related Boston College criminal proceedings, it is clear that the instant allegation is not based on a single iota of evidence.
"Such allegations published on an international scale are not only unjustified, but they are odious insofar as they seek to cause our client immeasurable harm in exchange for greater streaming success.
"Our client has now been forced to initiate legal proceedings to hold Disney to account for their actions."
Disney+ has been contacted for comment.
