#OnThisDay in 1974 the #liveAction #AdventureSeries #Shazam! debuted produced by #Filmation & airing on #CBS on #SaturdayMornings for #3seasons starring the #comicBookSuperHero #TheOriginalCaptainMarvel portrayed by #JacksonBostwick & #JohnDavey & his #alterEgo #BillyBatson portrayed by #MichaelGray