AM I the only viewer in Britain not to be entranced by Broadchurch (ITV, Mondays)? This murder thriller has returned, receiving universal plaudits that eclipse even the rapturous praise showered on the first series.

It certainly has many excellencies to be savoured: a fantastic cast; acting of the highest quality; an intelligent script; well-drawn characters; and, above all, brilliant contrast between the apparent idyll of the setting and the reality pulsating beneath the surface. It is not just the shocking murder of a child which reveals the ugly side of human nature: the crime lays bare ever-spreading waves of secrets.

The problem is not the dialogue, but the twists and turns of the plot. Everything had seemed resolved at the end of the first series, with the establishment and admission of the murderer as, terribly, the husband of the local policewoman, the wondrous Olivia Coleman. Now, as the trial begins, however, he retracts his confession, reawakening anger and suspicion in this tight-knit community.

Broadchurch suffers by comparison with another crime drama: Spiral (BBC4, Saturdays). This French import, a merciless flaying of the dark horrors masked by the tourist image of Gay Paree, is superior in every vital way.

Its story has an entirely different sense of inevitability. When, in Broadchurch, the kindly vicar asks the accused why he has changed his plea, the prisoner mutters darkly: "Everyone has a secret," and you just know that each episode is being set up, as character after character is found to have hidden something or other that points to guilt or collusion, only to be cleared in time for the closing credits, so that the process can be start all over again the following week.

The plotting misses that sense of unfolding necessity essential to good drama. Spiral has an inexorability about it: the patterns of crime become more and more confusing until a resolution that will make uncomfortable sense.

The main characters have a wonderful chemistry that sparks from the screen: respect, disgust, care, and manipulation are all in play. I do not know whether callous ambition, political infighting, and widespread corruption constitute an accurate portrayal of the Parisian judiciary and police force, but they create a fantastically layered context for the crime.

The flawed heroine cop Bertaud is pregnant - by whom, she is not sure - and this unwelcome condition brings about a new and believable softening of her hardbitten commitment. The moral and emotional complexities are ratcheted up another notch, but without overwhelming the actual story. I think it's terrific.

Life On A Mountain: A year on Scafell Pike (BBC4, Wednesday of last week) was a wonderful collage, the narration by a succession of people for whom the highest mountain in England is home, workplace, or where their hearts beat most warmly.

And there were not just people, but creatures: the native Herdwick sheep were hailed as the reason why the land looks the way it does; and, of course, there is the unmatched glory of the scenery. This native product would see off any import from Johnny Foreigner.