From a middle-aged pin-up to Lady Macbeth (twice), a shoot-em-up gangster to the Queen of England, a malevolent educator to an insouciant gossip columnist, no role seems to be beyond the reach of Dame Helen Mirren. The actress joins the affable Jim Carter (or Mr. Carson, as we know him from “Downton Abbey”) in conversation at the Kiln Theatre in North West London. A one-off fundraiser on February 16, all proceeds from the evening are going directly to the theater and its mission to make the arts more accessible to the neighborhood and surrounding community. —B.A.