Bobby (Patrick Duffy) enlists the help of his brother, Gary (Ted Shackelford), to fight J.R. (Larry Hagman) and John Ross (Josh Henderson), in this week's episode of Dallas (7 and 9 p.m., TNT).Gary, you may recall, is the middle Ewing brother - between J.R. And Bobby - and his character was spun off into "Knots Landing." And this marks the first crossover between the two branches of the family since Bobby stepped out of that shower alive in May 1986.As you may recall, Bobby had been killed in May 1985. And his death had consequences on "Knots Landing" - Gary went into a funk, allowing Abby (Donna Mills) to manipulate him more than usual. And Val (Joan Van Ark) named one of her babies after the late Bobby.When "Dallas" writers erased a season of that show, reviving Bobby, the "Knots" writers couldn't erase a season of their show. So while "Dallas" ran another 135 episodes and "Knots" ran another 184 episodes, there were no more crossovers. Until now.Oh, and, by the way - J.R. is about to join the actor who played him in that big ranch in the sky.Elsewhere on TV ...NBA (6 p.m. ROOT): Utah Jazz at Milwaukee BucksThe Bachelor (7 p.m., ABC/Ch. 4): In the traditional "Women Tell All" episode, the claws come out. Meow!The Biggest Loser (7 p.m., NBC/Ch. 5): Tim Gunn arrives to help with makeovers.Bones (7 p.m., Fox/Ch. 13): A young man's remains are found in a barrel in a hazardous waste disposal facility.The Carrie Diaries (7 p.m., CW/Ch. 30): Carrie gets a cover story for her latest night out on the town.Rules of Engagement (7:30 p.m., CBS/Ch. 2): Jeff and Audrey fear they'll be boring after they become parents. (Get a clue - you're boring now.)Monday Mornings (8 and 10 p.m., TNT): Sydney criticizes Lieberman for a misdiagnosis.The Following (8 p.m., Fox/Ch. 13): Joe Carroll tries to get transferred to a different prison.90210 (8 p.m., CW/Ch. 30): Liam decides to open a surfboard shop.Lost Girl (8 and '11 p.m., Syfy): A succubus feeds on the sexual energy of mortals.Deception (9 p.m., NBC/Ch. 5): Robert begins to suspect Joanna's motives.Switched at Birth (9 p.m., ABC Family): This episode is entirely in American Sign Language (with captions for the hearing).