But her presentation has always been stylised and conceptualised - from the diamond-encrusted diva of I Am Not A Robot to the "American archetypes" she portrayed in the Electra Heart project.
So it's refreshing to see this unvarnished acoustic performance of her new single, Happy. The video is as naked as the lyrics, as Marina quietly describes her struggles with sadness, and how she found sanctuary.
As I said last week, Happy is a fragile and beautiful song. But I've also worked out what was niggling me about the melody: The "I believe" section really reminds me of Dire Straits' Romeo and Juliet (specifically the line "Juliet, when we made love you used to cry").
Which isn't necessarily a flaw.