A Hell of a Wedding (2016)

Reza and his family attend the wedding of the brother of the mysterious Manouchehr, who returned to Iran after many years abroad to organize a huge wedding party. The first disappointment of the evening comes when the boys discover the space reserved for the children: an enclosed hall at the end of a garden, far from the food and the fireworks and under the surveillance of a weird grumpy man in a Minion costume. Reza and the rest of the children immediately try to escape the boring facility they were confined to, and when they decide to ruin the party at all costs they discover they are interfering with Manouchehr's plans, which are much bigger and more dangerous than theirs.

Unfortunately the movie A Hell of a Wedding is not yet available on HBO Max.