This year, the Frank Capra Christmas classic "It's a Wonderful Life" features former President George H.W. Bush in a major role.
He cannot be seen, but he can be heard by viewers whose televisions come equipped with the secondary audio program option.
The new version of "It's a Wonderful Life," including Bush's narrative, first aired on Dec. 7 and will repeat Tuesday at 8 p.m. on NBC.
The movie's video description, provided by TheatreVision, is available on a separate track that allows blind and visually impaired viewers to hear a description of the on-screen action.
The secondary audio feature must be activated by the television's remote device. Most newer sets come equipped with the technology, which often is used to add a secondary Spanish-language audio track to television programs.
The described audio feature was introduced in 1985 by WGBH in Boston, the PBS station that developed Descriptive Video Service, the first of its kind.
According to Larry Goldberg, director of the National Center for Accessible Media, several companies offer such service, and each offers something unique.
TheatreVision was the first to provide descriptive service in movie theaters; it is available at some movie houses in Los Angeles and Burbank.
The company often uses celebrities to provide narration, including Samuel L. Jackson, Pat Morita, Katharine Hepburn, Monty Hall, William Shatner and Angie Dickinson.
Using celebrities and people who portrayed characters in a movie to describe action adds a "different touch of excitement," said Helen Harris, president of RP (retinitis pigmentosa) International, the developer of TheatreVision.
However, most of the widely used descriptive services prefer not to use famous personalities.
"We do not believe in celebrity narrators. That calls much too much attention to the narration," said Goldberg. Instead, WGBH and the National Captioning Institute in Vienna, Va., use voice-over artists who are trained not to be intrusive.
The Narrative Television Network, situated in Tulsa, Okla., has been providing descriptive audio since 1988. Jim Stovall, the company president, said it uses four full-time narrators. Stovall, who is blind, said it is important that the listener recognize the voice of the person doing the describing and not confuse that narrator with one of the characters.
In addition to the four larger services, some smaller organizations describe action for live theater and industrial tapes, Goldberg said.
There are approximately 6.3 million blind and visually impaired people in the United States, according to the National Health Interview Survey conducted in 1994-95.