Dick Tracy ... before he dicks you (good night!)
Chester Gould's often violent strip (premiering in 1931) was wildly inventive with its depiction of the outward manifestation of evil in his villains' face and bodies. Flattop Jones, Pruneface, Shoulders ... you can just picture them even if you've never seen the strip. It is a major disappointment (to me, anyway) to discover the 2-way wrist-radio was not invented until 1946. Having said that, Dick Tracy can be credited as the first "true crime" strip, featuring a crime committed, followed by Tracy's detective work, often resulting in the pursued criminal to commit an even more heinous crime, concluding (eventually) with some kind of outrageous and deadly gunfight.
Then there was his relationship with the frustrated Tess Trueheart. It doesn't help that the very first caper in Dick Tracy was Tess being kidnapped and her father murdered. Really Chet? Murdered?
By 1936 there was already a radio drama of the strip.