Jack Starbright is the deuteragonist of the Alex Rider book series by Anthony Horowitz.
She is Alex Rider's American caretaker, closest friend and companion and the only adult who he trusts. In the books, it is revealed she has an older sister and three niblings who are unmentioned. It is Also unknown what her name is short for but Alex assumes it night be short for "Jacqueline." She first appears in the novel Stormbreaker. She also has dual citizenship in both America and England, thus preventing her from being taken out of the country.
Alicia Silverstone portrayed her in the film version of Stormbreaker. While in the novels she is a red-head, in the movie and the graphic novels Jack is blonde.
She is portrayed by Ronke Adekoluejo in the TV series.