The pros and cons of religion are at the core of The Gardener, a heady documentary that Iranian director Mohsen Makhmalbaf made with his son, also a moviemaker. The two traveled to the Bahai Faith headquarters in Israel on their quest to understand the meaning of religion and why it’s become “the cause of war.” “I’m investigating to see how much of the violence in the world can be attributed to religion,” says Makhmalbaf, an avowed agnostic. The film makes its Cleveland premier tonight at 7 at the Cleveland Museum of Art. It screens again at 1:30 p.m. on Sunday. Tickets are $9. (Niesel)