I think it is an Acanthus. I don't know much about it though.
Acanthus or bears breeches
Acanthus are robust herbaceous perennials with handsome, lobed foliage and tall, erect racemes of two-lipped flowers with colourful bract
A. mollis is a vigorous plant with large, glossy dark green leaves, pinnately lobed and, in late summer, tall racemes of white flowers with dusky purple bracts