Playwright Mia McCullough’s dark, witty new play, “Household Spirits,” is a ghost story through and through, but the mental health struggles, addiction and grief that haunt its characters are every bit as scary as the mysterious noises and doors that refuse to stay shut. In its world premiere at Theater Wit, Eileen Tull directs a fantastic cast that pulls off humor, pain, familial dysfunction and bizarre plot twists equally well. Set within commuting distance of New York City, the play centers on a wealthy family that includes power couple Philip (Doug MacKechnie) — recently enrolled in Alcoholics Anonymous after being...