Natural World: Perfect Shark, BBC Knowledge, 9.45pm
SOMETIMES evolution catches something of a break. This program begins, as so many do, with inane questions about which shark is the ''ultimate'' and lots of talk of ''design'' rather than adaptation. Then, 45 minutes later, it unexpectedly arrives at the right answer: there is no ''ultimate'' shark, because all sharks are perfect for the niches they occupy, and because no species survives forever. If only we could have established that up front. Anyway, it turns out to be an interesting program full of great footage of sharks in the wild and some good CGI that brings to life extinct species and particularly elusive existent ones. Among these is the modern cookie-cutter shark, which bites golf ball-size chunks out of whales, dolphins and tuna, and the extinct helicoprion, which had a strange, circular whorl of teeth that might have been used to break into hard-shelled prey.
Haven, 13th Street, 11am
AUSTRALIAN Claudia Black (Farscape) makes quite a menacing guest appearance in this American supernatural drama loosely based on the Stephen King novel The Colorado Kid. The town of Haven, Maine, is a magnet for folks with supernatural abilities, and the trio of former FBI agent Audrey (Emily Rose), local cop Nathan (Lucas Bryant) and smuggler Duke (Eric Balfour) work hard to keep things from degenerating into deadly chaos. This two-parter has Black's character running a gang that murders people and then resurrects them after extracting payment from grieving relatives.
Unlikely Animal Friends, Nat Geo Wild, 8.30pm
Cuteness abounds as we meet a cat that's friends with an owl, a deer that grooms a lynx, and a leopard who's pals with a rabbit.
Leverage, SoHo, 9.30pm
The poor man's Hustle continues with the team trying to take down a scientist who stole his research partner's discovery.
Kirstie & Phil's Vacation, Vacation, Vacation, LifeStyle, 7.30pm
Kirstie Allsopp and Phil Spencer head to Iceland, Morocco and Italy.