On Marylebone Road at Marylebone High Street, by Estcourt J Clack FRBS, 1960. The plaque above the mural reads "While living in a house on this site Charles Dickens wrote six of his principal works. Characters from which appear in this sculptured panel.".
The characters depicted are, left to right, top line: Scrooge, (the head with the door knocker represents Marley's ghost) Barnaby Rudge, Little Nell and Granddad, middle line: Dombey and daughter, Mrs. Gamp, bottom line: David Copperfield, Mr. Micawber. The large head is Dickens himself. Thanks to the London Remembers web site
Link for this information.