Flexor Hallucis Longus bends the big toe when you curl up your foot. It is called 'Hallucis' as the word Hallux means great or big toe in latin. This muscle also supports the longitudinal arch of the foot.
Origin - Lower 2/3 of the posterior surface of the fibula.
Insertion - Plantar (sole of the foot) aspect of the base of the distal (furthest) phalange of the big toe.
Actions - Flexion of the big toe.
Innervation - Tibial nerve.
Daily uses - Pushing off the surface in walking.
Example stretches - Soleus stretch.