The Knocked Up star got close to the Danish actor when they played a married couple in upcoming comedy The Other Woman, but she developed an irritating rash shortly after they puckered up for the cameras.
Producers feared Coster-Waldau's aftershave had caused the reaction so they ordered him to wash it off, but Mann suffered another allergic outbreak on the following take.
She tells British magazine You, "(I'm) allergic to Nikolaj Coster-Waldau... He's so handsome and I thought, 'This is going to be fun, I get to kiss him!' Then he kissed me and I broke out in hives. They thought it was his aftershave, so they washed his face and we did the scene again. The same thing happened. Isn't that weird?"