Jessel was Data's housekeeper with a British accent in an unknown, alternate future timeframe, when he was a Lucasian Chair professor at Cambridge University.

Data noted that although she was "trying at times" (when she likened the new style of his hair to that of a "bloody skunk," for example), she made him laugh.

She had her tea making skills questioned, bordering on insulted, by Jean-Luc Picard when he stated her Earl Grey tasted like Darjeeling. (TNG: "All Good Things...")