Nine months and one day after the third season finale, the fourth (and possibly final) season of Community (7 p.m., NBC/Ch. 5) begins.Before the show's small-but-incredibly loyal fan base complains, the fact is that, based on its ratings, the show should never have come back for a fourth season. (For a second or third season, for that matter.)It would be a huge surprise if "Community" lasts much longer, so enjoy it while you can.In this week's episode, Dean Pelton pits the students against each other.Elsewhere on TV ...Women's college basketball (6 p.m., BYUtv): San Diego at BYUThe Big Bang Theory (7 p.m., CBS/Ch. 2): Sheldon and Leonard get in a big fight with each other.American Idol (7 p.m., Fox/Ch. 13): Hollywood week continues..The Vampire Diaries (7 p.m., CW/Ch. 30): Shane leads an expedition to find the secret cure.Project Runway (7 and 11 p.m., Lifetime): The contestants create outfits for host/judge Heidi Klum.Two and a Half Men (7:30 p.m., CBS/Ch. 2): Jake brings his 36-year-old girlfriend home for a visit.Parks and Recreation (7:30 p.m., NBC/Ch. 5): Ben asks Tom, Chris and Ron to help him select a wedding caterer.Person of Interest (8 p.m., CBS/Ch. 2): A billionaire who's the latest POI might expose what Finch and Reese are doing.Grey's Anatomy (8 p.m., ABC/Ch. 4): The staff resents new policies at the hospital.The Office (8 p.m., NBC/Ch. 5): Staffers pair off into pretend couples so they can take advantage of a Valentine's Day discount.Glee (8 p.m., Fox/Ch. 13): Kurt confronts Rachel about what a bitch she is.Beauty and the Beast (8 p.m., CW/Ch. 30): Cat fears Alex and Vincent's lives are in danger.1600 Penn (8:30 p.m., NBC/Ch. 5): Skip's attempt to calm a group of protestors goes terribly wrong.Elementary (9 p.m., CBS/Ch. 2): Watson fears for Sherlock's sobriety.Scandal (9 p.m., ABC/Ch. 4): David learns the truth about the Cytron case.Do No Harm (9 p.m., NBC/Ch. 5): Jason wakes up to discover Ian has caused trouble with a drug dealer.Men's college basketball (9 p.m. BYUtv): BYU at San DiegoAnger Management (10:30 p.m., FX): Jennifer moves in with Charlie.Archer (11 p.m., FX): Gangsters chase Archer and his new stepfather.Suits (11 p.m., USA): Hardman files an outrageous lawsuit against Jessica.Legit (11:30 p.m., FX): Jim gets in a fight with another airline passenger.