Dean O'Dell (guest star Ed Begley, Jr., "Arrested Development") reinstates the Greek system on campus and, determined to solve the campus rape case, Veronica, along with Mac, Wallace and Piz, attends a party armed with coasters designed to test for drugs in the drinks of her peers. Meanwhile, Dean O'Dell hires Keith to investigate whether or not his wife is cheating on him. Jason Dohring, Ryan Hansen, Francis Capra, Michael Muhney and Julie Gonzalo also star.Series mastermind Rob Thomas writes and directs. 9 p.m. Tuesday. The CW.