Eva and Jackie are friends for life. Together with Thomas they've built a secret hide-out. Eva's parents are always fighting, sometimes they don't speak to each other for a week, so the three decide to punish the parents. They decide Eva will run away from home.
When Eva thinks about the plan, she finds a letter in the garden of the Colonel. The letter brings trouble for Eva and she suddenly disappears for real.
When she turns up several days later, she is very silent and looks at her father with even more distrust.
While on school camp, Eva, Jacky and Thomas decide to go to the address of the letter and find out who the mysterious Mr. van Pasen is. Because it's a bit far they decide to take the bus.
When they arrive in Veenendaal, they start asking around for the the address, because they have no clue where it is.
Eventually they find the address and Jacky is chosen as the lucky one to ring the bell.