paragraph: Amateur tennis star Guy Haines wants to divorce his vulgar and unfaithful wife Miriam , so he can marry the elegant and beautiful Anne Morton , daughter of a senator .  While on a train to meet Miriam , Haines meets Bruno Anthony , a forward stranger who recognizes Guy from gossip items in the newspapers that detail his marital problems .  During lunch in Bruno's compartment , Bruno tells Guy about his idea for the perfect `` Criss-cross '' murder : he will kill Miriam and in exchange , Guy will kill Bruno's father .  Since both are strangers , otherwise unconnected , there is no identifiable motive for the crimes , Bruno contends , hence no suspicion .  Guy hurriedly leaves the compartment but leaves Bruno thinking he has agreed to the deal .  Guy accidentally leaves his cigarette lighter behind , a gift from Anne to Guy , Which Bruno pockets .  Bruno heads to Guy's hometown of Metcalf and follows Miriam and her two beaux to an amusement park , where he briefly illuminates her face with Guy's lighter , then strangles her to death .  Guy's problems begin when his alibi an inebriated college professor on the same train as Guy can not remember their meeting .  But they increase exponentially when Bruno makes repeated appearances into Guy's life as he seeks to remind Guy that he is now obliged to kill Bruno's father , according to the bargain he thinks they struck on the train .  Bruno sends Guy the keys to his house , a map to his father's room , and a pistol .  Soon after , Bruno appears at a party at Senator Morton's house and hobnobs with the guests , much to Guy's apprehension and Anne's increasing suspicion . 
question: Why does the amateur tennis star Guy Haines want to divorce his wife Mirriam
answer: Mean