I thought they were fine. Not great, but not detrimental.
Straightedge means I'm better than you.

There's a lot of dialogue re-recording throughout so that hinders the performances of everyone, but it's especially hard on Lack. His voice almost hovers on its own in the mix, yet I still enjoyed his performance. So much of the role is grounded in his expressions so it works in that respect.
Musings of a Film Overanalyzer
http://criticismsandpraise.blogspot.com

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He wasn't just dull, his dialogue delivery was stilted and awkward. Not in a "I'm a mentally unstable outcast from society" way, just in a "I've somewhat memorized the script and now I'm going to try to speak my lines of dialogue" way. No need to struggle to justify it with nonsensical reasons. He simply had no acting talent. But I'm sure he's a swell guy once you get to know him. It's OK, the movie was not hinging on whether or not he could act. Scanners kicks ass regardless.

There are interviews with both Lack and Ironside on the new Criterion release. They both talk about Lack's acting - very interesting interviews.
In heaven everything is fine.

The leads were fine. O'Neill had a severely underwritten role but did her best to bring some urgency to it. The knockout is Ironside of course, he had the look and attitude and a lot of subtlety. Cronenberg isn't really a good director of actors in my opinion, he apparently asks them to bring a lot to the table, sometimes they can (Samantha Eggar, Genvieve Bujould, Deborah Harry, Patricia Arquette mostly women now that I think about it) and sometimes they just don't (James Woods not a good performance, but a landmark film).

His acting didn't bother me, as O'Neill's character says at one point "you're barely even human!". I think Lack probably was a bad actor, but this worked well with the character.

supposed to be, not suppose to be.

^this

Many things might be beyond your comprehension.

ACTING. It was and is possible for an actor to act the part of a vagrant/mental patient, be believable and exude some charisma.
This man had nothing going for him. He was just shoved in front of a camera and he recited the script.
Why Cronenberg shot his own film down, not to mention insulted the professional actors involved is beyond my comprehension.

He was suppose to be a vagrant/mental patient.The acting makes sense in the context.

It was bad. It was very bad. He broke suspension of disbelief every time he was on screen and unfortunately that was the whole damn film.
The other people were very good actors so that made the film slightly workable but he killed whatever buzz they managed to build.
He was awkward, hyper aware of the camera, had a careless attitude and just sucked the air out of the room in general.

i always liked stephen lack's performance. it's unique and quirky. i think cronenberg knew what he was doing when he cast him.

He didn't bother me at all

IN the commentary, not on the commentary.

Commentary? Which DVD/BD edition has a commentary track? Lack was/is an actor, he had several film credits prior to 'Scanners'. Granted his main "career" has been as a painter, though that shouldn't diminish his film work in any way.

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It's said on the commentary that Stephen Lack wasn't actually an actor, so I'd say he did pretty good in the role.

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