When his son is kidnapped, an overprotective father must go on a long and tough journey to find his son.

This works – character, event and action are all in place! However, it would be nice to get something about why this journey is meaningful for the father – “must face his fears” or something along those lines. Also, the repetition of the word ‘son’ makes the read a tiny bit clunkier – try changing it to ‘him’ or ‘child’ the second time.