A new season of Big Brother (7 p.m., CBS/Ch. 2 ) begins. So we get a new group of people who behave badly to win big bucks.Sigh.Elsewhere on TV ...MasterChef (7 p.m., Fox/Ch. 13): Contestants have to cook with an unexpected ingredient.Franklin & Bash (7 and 9 p.m., TNT): Peter's mother is arrested.Family Tools (7:30 p.m., ABC/Ch. 4): Stitch's new boyfriend is jealous of Jack.The American Baking Competition (8 p.m., CBS/Ch. 2): The competition continues.How to Live With Your Parents (For the Rest of Your Life) (8:30 p.m., ABC/Ch. 4): Elaine takes a part i/n Max's play reading in the final episode of this canceled show.Melissa & Joey (9 p.m., ABC Family): Joe inadvertently wrecks Mel and Austin's weekend plans.Baby Daddy (8:30 p.m., ABC Family): Ben and Tucker pretend they're a couple to get Emma into a good preschool.Royal Pains (10 p.m., USA): Hank investigates Boris' death.Futurama (11 p.m., Comedy Central): Fry is marooned on a distant planet.Necessary Roughness (11 p.m., USA): Dani helps a basketball player.Hot In Cleveland (11 p.m., TV Land): Elka gives Penny advice.The Exes (11:30 p.m., TV Land): Holly has to choose between poker night and date night.