TV highlights: The final four perform on 'So You Think You Can Dance'

The final four dancers -- Zack Everhart Jr., Jessica Richens, Valerie Rockey and Ricky Ubeda -- perform with all-stars from previous seasons, including Aaron Turner and Kathryn McCormick on a live, two-hour "So You Think You Can Dance" (Fox at 8 p.m.). In addition, "Modern Family's" Jesse Tyler Ferguson joins the judging table and Jason Mraz performs.