Boris Karloff's most famous role as the monster in Frankenstein (US, d. James Whale, 1931) made him a legend but it did little - or perhaps too much - for his career; he is far more memorable as Ned in The Criminal Code (d. Howard Hawks) earlier the same year.
The actor (born William Henry Pratt in London) began his screen career in the US in 1916 with The Dumb Girl of Portici (d. Lois Weber) and, in all, made 164 feature films, mostly American. The British-made The Ghoul (d. T. Hayes Hunter, 1933) was no doubt influenced by his US success in the horror genre, as were some later UK appearances.
He also had a TV series, Colonel March of Scotland Yard (ATV, 1954-1955), three episodes of which were compiled as the feature, Colonel March Investigates (d. Cy Endfield, 1953).
Brian McFarlane, Encyclopedia of British Cinema