This is a TV adaptation of a stage play written by Miroslav Hornícek.
Three thieves become servants to look for a treasure in an old house owned by Miss Matylda, but they have hard times to obey old lady's orders.
The story line is quite simple (it was originally a stage play, after all), but there are many predictable and unpredictable story twists, so you'll be probably surprised with the ending.
And of course, I like the dialogues.