The Krypton Factor (ITV1, 7.30pm); Jonathan Creek (BBC1, 9pm); Agatha Christie’s Marple (ITV1, 9pm)

A FACE-OFF of the supersleuths pits Jonathan Creek against Miss Marple tonight in a brain box special.

Add the return of The Krypton Factor, or “Britain’s toughest quiz” as it’s introduced, and you need to keep your wits about you to survive a night in front of the box.

The toughest part of The Kryton Factor is having to listen to host Ben Shephard orchestrate proceedings. They might as well employ a computer for all the excitement he injects into the fun and games of a show returning to the screen after 14 years.

This is a Factor without X appeal. The best thing is seeing how visibly shocked the cocky contestants are as they emerge from the mental ability round.

Investment banker David admitted he was “very surprised how tough it was”, while Cambridge University student Jonathan found the round “absolutely nerve-wracking”.

The intelligence test foxed several of them. This involved making the word KRYTON from letters they could only see on a screen. Shephard explains that “right is wrong” and that “the right hand is the left hand”. David found out the hard way, getting the letters back to front and upside down.

More punishment is handed out in the assault course on the Yorkshire Dales.

The contestants have to overcome 13 different obstacles. The youngest, Jonathan, staggered across the finishing line “nearly broken”.

Age hasn’t diminished Jane Marple’s ability to solve a murder. Nemesis marks Geraldine McEwan’s last outing as Agatha Christie’s spinster sleuth (before Julia McKenzie takes over the role) and what a rip-roaring case it is.

This one is stuffed to the gills with familiar faces, several of whom have barely a couple of lines to say before being murdered.

There’s Amanda Burton in a wimple, Ronni Ancona, George Cole, Johnny Briggs and Graeme Garden, to name but a few.

Richard E Grant is along for the ride, as companion to Miss Marple, who has been bequeathed two tickets for a bus trip with Daffodil Tours by old friend, Mr Rafiel.

A cryptic message suggests a murder has, or is about to be, committed. Before many miles have been travelled, passengers are dropping dead. “Coach parties are meant to be sedate affairs, this is more like Tosca,” notes one of the operalovers among them.

Anne Reid, last seen in a TV film playing Barbara Cartland, is on board as mother superior Sister Agnes, who knows that “thwarted desire can unleash evil even in the best of souls”.

By the second day, two of the passengers are dead, which is something that never happens on a Wallace Arnold coach trip.

Alan Davies is back as illusion designer and part-time sleuth Jonathan Creek after a four-year absence in a who, what and whydunit that plays about with the old haunted house and disappearing from a locked room plots.

Writer and director David Renwick takes us to Metropolis, a dark old house where the attic has become known as the nightmare room. For good reason – people who’ve spent the night alone behind the locked door have mysteriously disappeared without trace.

The only clue is a sticky secretion left in the bed, generally reckoned to be ectoplasm.

Creek has a new companion, Joey (Sheridan Smith, from Two Pints Of Lager And A Packet Of Crisps), who seems to know more than him about tricks and illusions, but still manages to need rescuing at a climactic moment.

There’s also some nonsense about Adam Klaus, the illusionist whom Creek advises, moving into making 3D porn movies that could easily be removed without loss.

This would also help reduce the overlong two-hour running time, during which my attention wandered more often than it should have done.