It sounds like you're after "The Wizard", screened in 1986.
The blurb is as follows;
Simon McKay is a genius inventor with dwarfism who chooses to spend
his life as a philanthropist and innovative toymaker dedicated to
preserving and protecting innocence. CIC agent Alex Jagger is assigned
to protect Simon from the evil forces who wish to use Simon's genius
for their own nefarious purposes.
They are soon joined by Simon's long
time friend, Tillie Russell. Simon, Alex, and Tillie become a family
unit working together through adventure and adversity, especially when
it comes to defeating Simon's self-proclaimed arch-enemy, Troyan, who
would rather seek revenge upon the world for his suffering from the
radiation poisoning he brought upon himself than take responsibility
for his own actions.