Tragedy
If you're looking for a laugh-out-loud, fun-for-the whole family good-timey romp, don't read Mourning Becomes Electra. We might stop scowling for a sec when we see Peter, Hazel, Orin, and Lavinia chatting it up in The Hunted—that is until Orin starts talking about bashing in skulls and ripping out intestines. We might even crack a smile at the loveable Seth Beckwith clowning with his pals when nobody but us is looking in The Haunted.
But there's not a whole lot of fun in O'Neill's trilogy. Instead, we've got deceit, incest, insanity, murder, suicide, and a whole lot of evil and hate. We've got characters destroyed by their character flaws. Any way you look at it, the story of the Mannon family is a tragedy for sure.