Maryam d'Abo was 20 in Xtro when she played the character 'Analise Mercier'.
That was over 41 years ago in 1982.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 63, and has starred in 36 movies in total, 36 of those since Xtro was released.
In Xtro, I think Maryam d'Abo looks: