How to kill your Sister

After 8 years of silence, Anna finds herself on the doorstep of her older sister Kat in a car with a coffin mounted on the roof. Anna has cancer and wants Kat to accompany her on her last trip to Spain. Along the way Anna finally wants to find out why Kat abandoned her after the death of their parents. The closer they get to their destination, the harder it becomes for the sisters to hide the secrets they both harbor.