The Shell Seekers 9 p.m. Saturday, The Hallmark Channel
Vanessa Redgrave (above), who might be the busiest actress in showbiz, takes another spiritual journey.
Peter Perfect 9 p.m. Saturday, Style
The Simpsons 8 p.m. Sunday, Channel 25
Lisa's film about her family gets accepted into Sundance. Thoughtful documentaries are all the rage.
Dexter 10 p.m. Sunday, Channel 4
The more scripted crime shows return to TV, the more you realize how much better "Dexter" is than all of them.
RADIO, RADIO
This American Life 10 p.m. Sunday, Showtime
Showtime premieres the second season of its series, based on the public radio staple. I've always thought this show works better on TV: we get all of the benefits of Ira Glass's nerd-charm hosting style, and none of the self-absorbed musings of twentysomething quasi-journalists.
ON DEMAND
There's Something About Mary
Lowbrow gross-out humor from bad-taste kings Peter and Bobby Farrelly. But you won't be able to keep from laughing, especially at Matt Dillon's sleazy gumshoe hired by smitten but consummately hapless Ben Stiller to track down pretty Cameron Diaz, a magnet for obsessives. There's scarcely a bodily function that doesn't make the final cut. (R; runs through May 11)
