Tonight, CSI: Crime Scene Investigation (9 p.m., CBS/Ch. 2) does something very few scripted TV series have done before - it airs its 300th episode.And one of its former stars returns to mark the occasion. Marg Helgenberger is back a Catherine Willows to help the team solve a case that has haunted them for 14 years.Yes, "CSI" is in the midst of its 14th season.There's behind-the-scenes irony here. ABC's television studio developed "CSI," but the ABC network rejected the show for its lineup. "CSI" then moved to both the CBS studio and the CBS network where, along with its two spinoffs, it has run for a total of 729 episodes. And counting.ABC really could have used shows like that over the past few years.By the way, the other scripted TV series that have passed the 300-episode mark are:"Gunsmoke" - 635 episodes"The Simpsons" - 532 (and counting)"Law & Order" - 456"Ozzie & Harriet" - 435"Bonanza" - 430"Dallas" - 382 (and counting)"My Three Sons" - 378"Lassie" - 352"Danny Thomas" - 351"Knots Landing" - 344"ER" - 331"Law & Order: SVU" - 322 (and counting)Elsewhere on TV ...World Series (5:30 p.m., Fox/Ch. 13): Game 1 - St. Louis Cardinals at Boston Red SoxSurvivor (7 p.m., CBS/Ch. 2): Everybody's plans are changed when the membership of the two tribes is juggled. Utahn Tyson Apostol is still in the game, and - up to this point - he's doing pretty well.The Middle (7 p.m., ABC/Ch. 4): Mike and Frankie agree to drive a giant cow float in a parade.Revolution (7 p.m., NBC/Ch. 5): A man from Miles' past reappears.MLS (7 p.m., Ch. 30): Chivas USA at Real Salt Lake. With a win, RSL clinches no worse than second place in the Western Conference.Back In the Game (7:30 p.m., ABC/Ch. 4): Danny lets other kids cheat off his test.Criminal Minds (8 p.m., CBS/Ch. 2): Hotch fights for his life after being stabbed.Modern Family (8 p.m., ABC/Ch. 4): Gloria hires a male nanny.Law & Order: SVU (8 p.m., NBC/Ch. 5): A friend (of ADA Barba's is accused of rape.It's Always Sunny in Philadelphia (8 p.m., FXX): An experiment makes Charlie smarter.Super Fun Night (8:30 p.m., ABC/Ch. 4): Helen-Alice and Marika meet their idol.NBA preseason (8:30 p.m., ROOT): Utah Jazz at Los Angeles ClippersCSI (9 p.m., CBS/Ch. 2): Catherine Willows (Marg Helgenberger) returns to help with a case.Nashville (9 p.m., ABC/Ch. 4): Rayna wants to obtain the rights to her music.Ironside (9 p.m., NBC/Ch. 5): Ironside is forced to face a past mistake.Arrow (9:40 p.m., CW/Ch. 30): An escaped prisoner starts torturing and killing women again.The Tomorrow People (10:40 p.m., CW/Ch. 30): John wants Stephen to infiltrate Ultra's man computer.Top Chef (11 p.m., Bravo): The chefs get a crash course in Vietnamese culture.Duck Dynasty (11 p.m., A&E): The Robertsons host their church's annual trick-or-treat event. (Season finale)American Horror Story: Coven (11 p.m., FX): Fiona takes on an unlikely protégé.Key & Peele (11:30 p.m., Comedy Central): In one sketch, Mr. T teaches life lessons; in another, an insult comic crosses the line.