Alfred Hitchcock’s Psycho is now considered, if not the best horror film of all time, then definitely top 5. It is the original slasher film. SPOILER ALERT: In killing off Janet Leigh, its biggest star, 30 minutes into the film it shocked audiences and forever changed what was possible in cinema. On its original release, however, critics savaged the film. Audiences flocked to it, and critics changed their tune, but the fact remains one of the greatest masterpieces in film history was described by Time Magazine (and countless others) as ‘merely gruesome’.