Saving the planet
Celebrate Earth Day by catching the Oscar-nominated documentary "A Fierce Green Fire," an installment of "American Masters" that looks back on 50 years of environmentalism. Robert Redford, Meryl Streep and Ashley Judd are among the celebrities narrating. 8 p.m. TPT, Ch. 2
Love on the rocks
Tori Spelling, who seems to have given up acting to spend all her time analyzing herself, is at it again in "True Tori," a new docu-series about a marriage that's falling apart. Turns out no one advised her that reality TV is the best way to guarantee divorce. 9 p.m. Lifetime
Changing of the guard
Stephen Colbert brings his "truthiness" to "The Late Show With David Letterman," his first appearance on the program since it was announced that he'll be taking over sometime in 2015. Now all we need is an appearance by Jay Leno, who just has to stop by before Letterman calls it quits. 10:35 p.m. WCCO, Ch. 4
Neal Justin
