How many movies have IU and Seo Tai-ji acted in together?

They have worked on 1 movie together! Their first movie together was 서태지밴드 콘서트투어 '콰이어트나이트' (2015) and was their highest rated movie together. They have not worked together since 서태지밴드 콘서트투어 '콰이어트나이트' (2015).