I have not worn my mascara in the shower or underwater, so if that is your intention I cant attest to its effectiveness... I can say that all my mascaras were practicly melting off my eyes before I bought lancome hypnose drama waterproof mascara. Everyday I would come home and there would be mascara smudged under my eyes!!! Not once has this happened since I switched, and it stays put!! I need to use 2 makeup removers (sensibio and clinique) to remove it!
It also makes my eyelashes look amaze-balls!! Super long and thick!