Otroligt het!

Lisa is in middle age and married to Bertil. Yesterday she celebrated a step up in his career with the girls at the hotel in town. In which "happened" Lisa to have a hot love meeting with a younger man in the hotel's spa area. Meanwhile, Lisa's sister is on the way to proudly show off her new found young man. He was also staying at the hotel last night. Was it him? The friend and closest neighbor, Gerd, a gray, miserable and unemployed, single girl, wondering where Lisa stubbornly went yesterday? Panic begins to spread, the sister is coming. What should Lisa do? Does Bertil suspect anything? Will Gerd back her up or is she up to something else?