The phrase "a pair of documentaries" is correct and usable in written English.
You can use it when referring to two documentaries that are being discussed or presented together.
Example: "The film festival featured a pair of documentaries that explored environmental issues and their impact on society."
Alternatives: "two documentaries" or "a duo of documentaries".
His real role model, Mr. Winterbottom went on to say, was Ingmar Bergman, about whom he made a pair of documentaries.
And the ocean is where Mr. Cameron went to make a pair of documentaries that allowed him to score a rare trifecta of business, art and pleasure.
He produced a pair of documentaries — "The Murder of Fred Hampton" and, with Chuck Olin, "American Revolution 2" — that examined race, politics and civil turbulence in Chicago in the 1960s.
This year, "Wall Street: Money Never Sleeps," directed by Oliver Stone, and a pair of documentaries, "Inside Job," directed by Charles Ferguson, and "Client 9: The Rise and Fall of Eliot Spitzer," directed by Alex Gibney, all chronicle in one way or another the sins of a financial industry that lost its moorings.
The social and political upheavals of the nineteen-sixties are the subject of an extraordinary trio of new releases — a pair of documentaries by Mike Gray and Howard Alk, made in Chicago in the heat of the moment and released by Facets, and "The Hours and Times" (Choices), a 1991 drama directed by Christopher Münch.
He's also filmed a pair of documentaries about Cuba's former Communist dictator Fidel Castro.
When the Pixies reformed for a cash-in reunion tour in 2004, they hired a pair of documentary film-makers to record the event.
It's significant that the movie should have been directed by a pair of documentary-makers, Shari Springer Berman and Robert Pulcini, since it hovers knowingly between fact and fiction, incorporating documentary footage and animation alongside dramatised passages from Pekar's life.
In fact, the project has been in an indeterminate state for so long that it has been the subject of at least two books, hundreds of editorials and a pair of documentary films, including last summer's "Cape Spin" -- described by The New York Times as a "tragicomic" look at one of the nation's most protracted energy infrastructure battles.
In the 2000s Scorsese also directed a pair of musical documentaries.
While we congratulate ourselves for living in momentous times, a pair of PBS documentaries this week delve into events that are, without any doubt, historic.
