That Stranger (Polish: Ten obcy) is a novel by the Polish author Irena Jurgielewiczowa, published in 1961. It is an obligatory reading in year 6 in Polish primary schools. That Stranger had been translated into 23 languages. The novel was placed on the Honour List at the 1964 Hans Christian Andersen Awards. Major characters of this novel appear in another book by Irena Jurgielewiczowa entitled Inna?(Another?) (1975). A feature film had been created on the basis of Inna?.