Der Weihnachtsbrief blends sentimentality and social realism in the manner of the English novelist Charles Dickens, whose Christmas Carol (1843) had a huge international impact; and like Dickens' Scrooge, the little Ludwig in Pocci's play has only two books in his possession, including Robinson Crusoe. This Christmas play, quite apart from Pocci's puppet productions, nevertheless makes a small nod to the usual repertoire of Josef Leonhard Schmid's Munich theatre: for Ludwig's only toy is... a Casperl puppet.

The widow Werner lives with her young son Ludwig in misery: a sad Christmas is coming. To surprise her son, Mrs Werner goes out to buy a small pine tree and some apples. In her absence, Ludwig writes a letter to baby Jesus, asking for an illustrated Bible: he throws the letter out of the window addressing it to the angels. On Christmas morning, a package is delivered containing the Bible he asked for. The donor is Friedrich Walter, an old friend of the deceased Karl Werner: he has just returned from a long trip to the Orient and is inquiring at the police station about the widow's address, when some officers tell him of the amusing discovery of Ludwig's letter. Friedrich Walter takes the widow and child under his protection.