* The name is misspelled - Perhaps you're thinking of someone with a slightly different name.
* She is a relatively unknown actress - Many talented actors work in small roles or independent projects that don't receive widespread attention.
* She is a non-acting professional - There could be a person named Mary Farrell who works in a field other than acting.
To help me find information, could you please provide any additional details you may have, such as:
* Approximate age
* Specific type of project (e.g., film, TV series, theatre)
* Any other identifying characteristics (e.g., nationality, hair color, etc.)
With more information, I may be able to find the actress you are looking for.