South African-born director Roger Mitchell is known in the United States for lighthearted fare like Persuasion and Notting Hill, so it’s a pleasant surprise to discover that he can handle weightier subjects with equal aplomb.  Mitchell’s offhanded approach to storytelling is a considerable asset that prevents Titanic Town from playing like other films on the conflict in Northern Ireland. The Boxer and In the Name of the Father were solid movies that dealt with the Troubles in a grim, solemn manner. Titanic Town, however, seems fresh because it brims with a pungent gallows humor.

Set in 1972 Belfast, the film, which is based on Mary Costello’s autobiographical novel, initially treats the war with bemused detachment. Newly arrived in the Andersonville section of Belfast, the McPhelimy family find quickly themselves stuck in the middle of the fighting. British tanks roll through the streets, and the evenings are interrupted by gunfire. Curiously, it doesn’t seem to phase Bernie McPhelimy (Julie Walters, Intimate Relations), who chases an IRA gunman out of her yard because his presence endangers her family. When British soldiers demand to search her home, she becomes upset not because her house has been invaded but because she’s worried the soldiers will find her husband Aidan (Persuasion’s Ciaran Hinds) and her four children to be slovenly.

Bernie’s attitude abruptly changes when a close friend of hers dies while watching Bernie’s son. The other locals are content to blame the British despite the fact that the woman was actually killed by a stray IRA bullet. Bernie begins attending peace meetings and publicly blames the IRA. Soon bricks are flying through her window. Bernie doesn’t give up and goes on the radio asking to meet with IRA members to find out what happened and to convince them not to attack during the day when bystanders can get caught in the crossfire.

When the IRA actually honors her request for a meeting, Bernie winds up becoming a mediator between them and the British government. She instantly becomes a darling of the local media and a pariah at home. At first many of the locals assume she’s an informer, making Bernie’s children outcasts at school. Her adventures wind up aggravating Aidan’s ulcer, sending him to the hospital. Her daughter Annie (Nuala O’Neill in a terrific debut) suffers the worst, however. Annie can’t understand why her mother goes on television claiming to speak on behalf of her children when her children would like her to quit.