We all love a bit of suspense. A spin on the roulette table of hope. Hence the enduring popularity of the surprise film at the Dublin Film Festival each year (it was Steven Soderberg’s Unsane this year) Mystery Matinee is a low stakes gamble. In January you’d have got to see Ladybird, a month before its general release. In February you’d have got to see Nicholas Cage in Mom and Dad. Talking points are guaranteed off the back of parting with yer fiver.