In “Razorblade Tears” we have Ike Randolph, who did time for manslaughter back when he was “Riot” Randolph, taking the fall for a drug-gang pal. Like Bug Montage, Ike has remade his life and is running a successful landscaping business in rural Virginia, where Cosby grew up and which he knows so well. The sudden problem is that Ike’s 20-something gay son, Isiah, whose sexual orientation Ike hated, has been gunned down and killed on a Richmond street along with his husband, Derek. Ike is a beautifully wrought character who is racked with regret for not having accepted the boy he loved. When the police take their own sweet time investigating the murders, an enraged Ike hooks up with Derek’s father, Buddy Lee, who’s also guilt-ridden — and likewise an ex-con with a violent history — to track down the killers and execute them.