Cannes was treated to a grisly slice of black comedy with \"Sightseers\", the story of a pair lovebird serial killers who smear a trail of blood along the British tourist trail. The dark farce by Britain\'s Ben Wheatley -- who has a cult following for earlier movies like the horror flick \"Kill List\" -- tells the story of mousy Tina, a 30-something woman still living at home with her worry-wart mother. When she manages to land a lover, the bearded red-head Chris, he whisks her away in his beloved caravan to show her a proud selection of England\'s tourist treasures, from the Crich Tramway Museum to the Keswick Pencil Museum. But Chris is a stickler for details, who likes things just-so, and when fellow campers rub him up the wrong way, he has little choice but to kill them off one by one -- drawing eager-to-please Tina in his wake. Described by Screen magazine as \"a blissful bit of dark, funny and at times very bloody entertainment,\" the film screened to whooping applause in the Directors\' Fortnight section of the Riviera festival. \"For me it\'s a romantic, touching love movie, a rom-com -- with some violence in it,\" Wheatley told AFP on Thursday. \"It\'s about relationships and the negotiation between a man and a woman and what they like and don\'t like in the early part of a relationship. \"Unfortunately he likes murdering people and then she kind of joins in.\" Scripted by comedians Alice Lowe and Steve Oram, who also play the lead roles, the film features some excruciatingly gory scenes -- including a crushed head in the vein of Quentin Tarantino, which Wheatley fought to keep in. \"It provides a moral level to the scene, because otherwise you don\'t see the consequences of their actions,\" he said. Lowe said the project started \"as a joke, really,\" about characters who appear \"very geeky, but actually they\'ve got a dark secret.\" The pair drew on their own experience of rainy English family holidays -- their parents arguing in the front of the car -- for the script. \"Chris is a very British psychopath, he\'s very anal,\" said Oram. \"But there\'s a lot of restraint in British comedy,\" added Lowe. \"It\'s all about things slipping through the cracks. These characters go past that -- they break all the rules.\"