Ha, there's a difference between “I saw that good one” -- translated to Croatian, this wording strongly implies that both knew upfront which movie was good and

Ha, there's a difference between “I saw that good one” -- translated to Croatian, this wording strongly implies that both knew upfront which movie was good and he watched only that one. But according to the parent's explanation it may not be the case, Alice has only learned that one of the movies was good. and "The one I saw was good" (he picked a random movie from the collection and it happened to be good -- which would be "a good one" from the parent's example).