Mary Elizabeth Clarke was 52 when she was last seen in Niagara Falls, Ontario, on April 8, 1990.

There is no verified timeline of her movements after she was seen that day, no confirmed later sighting, and little publicly documented detail about any initial search, interviews, areas checked, or investigative theories.

For family and acquaintances, the long gap in publicly documented answers remains the defining feature of the case. If anyone knew Mary, saw her in Niagara Falls on or after April 8, 1990, or has information that could help, please come forward.