Back in London, Walls had substantial roles in "The Sunshine Girl" (1912); "The Marriage Market" (1913) and "A Country Girl" (1915). Later in 1915 he played Coquenard in a revival of Messager's "Veronique"; between then and 1921 he appeared in nine other musical comedies and a pantomime. His best known show of these years was probably "Kissing Time" (1919), in which he played Colonel Bolinger opposite Leslie Henson. His biographer, Sean Fielding, writes, "His forte was the portrayal of amiable philanderers or eccentric older gentlemen, usually with a forceful, even hectoring manner."