Morecambe and Wise. The Two Ronnies. Pete and Dud. Fry and Laurie. Mitchell and Webb. Barratt and Fielding. From the 1960s to the present day, the Brits have been kings of the comedy double act. But other than French and Saunders there have been few queens to add balance to the monarchy of mirth.

Step forward bright new hopes Watson and Oliver (BBC Entertainment, Saturday at 8.30pm), the first female comedy duo to be commissioned by the BBC in 25 years. In an endearing mix of live performance and pre-recorded sketches, Lorna Watson and cohort Ingrid Oliver hark back to the good ol' days of comedy revue shows: a time when all the family, from toddler to Gran, could chuckle together without fear of inter-generational embarrassment.

Bearing an obvious admiration for the aforementioned Dawn French and Jennifer Saunders, the two new girls on the testosterone block arrive on the back of three sold-out and critically lauded Edinburgh Fringe Festival shows. Unfortunately, they've forgotten to bring the jokes along for the telly ride. It's never a good sign when a comedy show relies on canned laughter, rather than actual humour, to spotlight the funny stuff. Don't be fooled: this is not one of those dumb but loveable "it's so unfunny it's funny" shows. Watson and Oliver are both likeable and talented comedic actresses but the writing is poor and childish. Many of the sketches seem lazily recycled and drag on forever; by the time we get to the "punchline" the horse has suffered so much flogging that even Tesco couldn't find a use for it.

That said, the first episode does have a saving grace in the form of Torchwood's perma-grinning, perma-tanned John Barrowman (above, with Watson, left, and Oliver). In the show's live musical climax the girls wisely allow Barrowman - doing a magnified, egocentric version of himself, tongue firmly wedged in cheek - to steal the show with a flurry of jazz hands and vocal theatrics. Maybe with a little time and perseverance I'll grow to love Watson and Oliver, but probably not as much as Barrowman's self-caricature loves himself.

Also taking inspiration from the television of yesteryear - this time cloning the DNA of Remington Steele and Moonlighting - is crime drama Castle, which returns to our screens for a fifth season (Fox, tomorrow at 8.55pm). Full of mystery and romance, Castle prides itself primarily on being fun to watch, but while it was certainly a cliffhanger, last season's finale wasn't exactly a barrel of laughs. With an attempted murder to contend with and feelings of betrayal flying around, no one was having a particularly good day until, that is, Detective Kate Beckett turned up on the doorstep of novelist Richard Castle and the two finally got it on after four whole season's of on-screen sexual tension.

This season's opener starts out with the awkward morning after, but despite the show having blown its "will-they-won't-they" cover, it maintains a heady brew of compelling storylines and character chemistry. What you see is what you get with Castle: kooky formulaic fun. Even the sex can't spoil it.

Dealing with a slightly more catastrophic morning after are the investigative scientists at the Anomaly Research Centre, where almost causing the end of the world puts a night of sexual consummation in the shade. The fifth and final series of sci-fi adventure drama Primeval (BBC Entertainment, Tuesday at 8.10pm) opens with a mighty sigh of relief over an apocalypse averted in the previous season. With past, present and future eliding and colli-ding as ever, the team continue to do what they do best - chase monsters; this time a scary burrowing creature that's bringing chaos to the city through tears in the space-time continuum.

With its impressive CGI special effects, Primeval romps along at a cracking pace and should suit both children and adults. This is family viewing that doesn't disappoint.