Hunted, BBC One

I daresay some of you, like theartsdesk, have been pining for the sadly departed Spooks. Its production company, Kudos, knows how you feel, and has rustled up this pacey, knotty and deliberately complicated thriller in its place.

The decision had clearly been made to seize the viewer's windpipe in a throttling grip even before the credits had stopped rolling, and the opening 15 minutes of this debut episode charged along like a herd of furious buffalo overdosing on amphetamines. We were in Tangier, armed with high-octane cinematography and a panicky sense of encroaching danger. Sam Hunter (played by pouty-lipped Melissa George) was engaged in an exceedingly hazardous mission to free a certain Dr Hill from a bunch of merciless-looking types who were trying to squeeze information out of him by painful means.

In finest Mission: Impossible style, nobody was whom, or what, they seemed. Sam was posing as the French-speaking lover of the villain-in-chief, before modulating into a plummy Home Counties tone when addressing the bedraggled prisoner. But by then we'd been convinced she was already dead, since she'd gained entry to the bad guys' lair by an outrageous scam in which she seemed to have been shot through the head by a sniper and left for dead. It fooled Mr Bad, who only discovered the ruse when he realised the fake blood he'd been spattered with tasted all wrong.

This wasn't all. Sam then had to survive a double-cross - or possibly a double-double-cross - and two waves of cold-eyed assassins before we left her gravely wounded in a beachside cafe. But (we learned) that all took place a year ago. Now here she was in a remote house in the Scottish Highlands, battling her way back to fitness by holding her breath underwater and running miles up hills and through forests. For relaxation, she scanned newspapers for carefully hidden secret clues.

What on earth was going on? Eventually writer/creator Frank Spotnitz (veteran of The X-Files and Strike Back) relented a little, and brought Sam back into gray, downbeat London. She went back to work with what is apparently a private security company called Byzantium, which somehow manages to marshall resources which would make the CIA feel pitiful and under-funded. All her colleagues, from stone-faced boss Rupert Keel (Stephen Dillane) to burly Deacon Crane (Adewale Akinnuoye-Agbaje, pictured above) and Aidan Marsh (Adam Rayner) believed she was dead, though her amazing return didn't inspire any of them to jump for joy or crack open the bubbly. Instead they were sullen and suspicious, but at the end of the day it's only TV drama, so despite everything Sam was promptly back on a new and highly sensitive case.

Looks like we're going to have two big themes running in parallel. Sam's new job is to infiltrate the household of snarling self-made tycoon Jack Turner (Patrick Malahide, pictured below), who's involved in some vast racket in Pakistan involving buying dams and controlling the water supply. She's making indecently swift progress, having already charmed Turner's son Stephen (Stephen Campbell Moore) into inviting her to live under the Turner roof as nanny to his young and motherless son.

Meanwhile, she'll be trying to work out who double-crossed her in Tangier, and whether that's the same person who Keel believes is the mole within Byzantium. Aidan Marsh, her former lover, has been the first to fall under Sam's accusing gaze, but what she doesn't know is that a despicable unnamed assassin from Tangier is now masquerading as a Dutch water scientist who has also just arrived at Jack Turner's door.

So Hunted is airborne and undeniably gripping, but it remains to be seen how it sustains over eight episodes. Setting up a mystery is much easier than bringing it to a convincing resolution. You get the feeling you're in safe hands here, though.