Zoe Wanamaker

I first saw this actress playing Susan Harper on My Family (http://www.imdb.com/title/tt0257315/), a critically acclaimed Brit-com.  She has guest-starred in both Dr Who and Harry Potter.
Here is her official site link: http://www.zoewanamaker.com/

Publicity Shot (found broadway.com/buzz)

As "the last human being" on Dr Who- multiple appearances, including Rose's first trip with the good doctor!
(The same image appears in several places, and I don't know who to attribute it to!)

Madame Hooch- Multiple Harry Potter Film Appearances-IMDb image; there are plenty if you run a Google Search- and I particularly enjoy the ones of her in goggles, refereeing Quiddich!