Complex sentence: In 1939, Warner Bros. released a cartoon short spoofing their "cycle" of crime films; the cartoon's title, "Thugs with Dirty Mugs", is a direct pun on "Angels with Dirty Faces".
Split into simpler sentences: In 1939, Warner Bros. released a cartoon short spoofing their "cycle" of crime films. The cartoon's title, "Thugs with Dirty Mugs", is a direct pun on "Angels with Dirty Faces".