Bassie and Adriaan take a well-earned holiday but find themselves chased by two diamond thieves, referred to as B1 and B2. The crooks mistake Bassie for the go-between who came to collect the key to the vault of the stolen diamonds.
Unfortunately the movie Bassie & Adriaan: The Secret of the Key is not yet available on HBO Max.
| Writing | Aad van Toor | Writer |
| Directing | Aad van Toor | Director |
| Editing | Rob Klein | Editor |
| Writing | Bas van Toor | Writer |
| Directing | Guus Verstraete jr. | Director |
