Sometimes Criminal Minds asks too much of its audience. It's not the show's premise that stretches credibility. Catching murderers through psychological profiling might look like modern criminological magic to the amateur but Sherlock Holmes was a master of that science more than a century ago. It's the cast.

Take Thomas Gibson. When I look at him I don't see sangfroid detective Aaron "Hotch" Hotchner, I see straitlaced Greg from the sitcom Dharma and Greg, and worry that his dippy hippie wife (Jenna Elfman) will burst in and bugger up a crime scene with her madcap Lucille Ball act.

And the show's star, Mandy Patinkin, who plays emotionally wracked criminal profiler Jason Gideon. I still can't get past Patinkin as the emotionally wracked (in a humorous way) Spanish swordsman Inigo Montoya in The Princess Bride (1987) let alone accept he's no longer emotionally wracked hotshot medico Dr Jeffrey Geiger from Chicago Hope.

Tonight we are asked to make the most ridiculous suspension of disbelief of all: James Van Der Beek as a religious fruitcake-cum-serial killer with a multiple personality disorder brought on by a cruel father.

Basset-eyed Dawson Leery a killer? As if. He handled six seasons of Dawson's Creek without topping his yes-no, on-off again girlfriend Joey Potter (Katie Holmes) or that useless droog of a best friend Pacey (Joshua Jackson), why would he now start murdering innocents and putting video of the killings on the internet as a warning to other sinners?

He hasn't been getting a lot of TV work since the series was canned, true, but surely that's an overreaction.