Half sequel and half companion to the previous Zanussi’s film "Life as a Fatal Sexually Transmitted Disease", "Supplement" focuses on frustrated medical student, Filip and his pragmatic girlfriend, Hanka.
Torn between a career as a doctor and the monastic life of a priest, Filip agonizingly wonders if he has truly received his calling or if he’s meant for the secular world. Standing by while Filip struggles to find the answer within himself, Hanka has her own inner struggle – can she bear to go through the motions of day-to-day life as he keeps her at a distance, o dose her love indeed have limits.
At a film set Filip meets old doctor Tomasz. An old cynic and an oversensitive youth do not seem a couple to match, but it is here that Filip finds spiritual support.