Writer-director Paddy Considine's "Tyrannosaur" is certainly bleak and depressing - I mean, (minor spoiler alert) a dog dies before the opening credits.

Writer-director Paddy Considine’s “Tyrannosaur” is certainly bleak and depressing — I mean, (minor spoiler alert) a dog dies before the opening credits.

But if you can slog past this downer of a script — and some moments of hard-to-watch brutality — there are two superlative performances in this bittersweet affair.

Joseph (Peter Mullan) is a bitter old man, consumed by bouts of rage and lots of alcohol. During a particularly dark episode, he takes solace in a Christian charity shop, where he meets Hannah (Olivia Colman).

The grizzled old man and the kindhearted Christian are unlikely friends, but revelations about Hannah’s home life hint that there’s a shared darkness in her.

Considine makes a stunning debut here. “Tyrannosaur” is a bit of a gut punch, sad and often cruel, but there’s an odd sweetness tempering it.

Mullan gives a challenging performance in the lead. He makes the sour character a difficult one for an audience to like, but then peels away Joseph’s layers. His character’s evolution melds perfectly with that of Colman’s, and her performance is no less stunning.

Be warned: I know thick British accents are a stumbling block for some. They are plentiful here.

“Tyrannosaur” is occasionally hard to watch. It’s equally hard to forget.