It’s almost Halloween and Dawn is out shopping with Carol. As Dawn is waiting for Carol, she hears a commotion from a nearby store. Somebody wearing a clown mask runs out of the store followed by a clerk who yells that they’ve been robbed. The robber jumps into a nearby black Chevy Cavalier and drives off. Dawn is questioned by the police about what happened and whether or not the robber saw her. Dawn is terrified by the experience and disappointed that the robber wasn’t caught. The parents of Palo City decided that it’ll be too dangerous for their kids to go out trick-or-treating with the robber on the loose, so they’ve instituted a curfew until he is caught.
Dawn discusses the robbery with the other members of the We Love Kids Club and decide to catch the robber. They first go over to the little variety store that Dawn had been shopping in before the robbery occurred. Even though it isn’t the same place that was robbed, they carry a lot of Halloween items & Dawn thinks that they might carry the kind of clown mask that the robber wore.
Unfortunately, the store doesn’t sell them, but the salesperson points Dawn & the other girls towards another store that’s only open during Halloween. When they go to the store, the clerk tells the girls the all of three of the clown masks were sold and he describes the buyers: a high school guy with long, brown hair who left on a skateboard, a person who drove away in a van from a nearby shop, and a woman. The girls eliminate the woman as a suspect, so they focus on the two male suspects.
The high school guy turns out to be one of the nicest kids in Palo City; he does charity work, helps old ladies & pets cross the street, and picks up little. The girls decide that he’s probably not guilty and they’re left without any more leads until they spot the car that was used in the robbery which has a bumper sticker on it from a local fast food place, so the girls decide to stake it out and see who comes & goes.
The cashier is a blond woman who looks a bit older than most fast food workers and the girls mention to her that they’re looking for a boy who drives a black Chevy with a bumper sticker from the restaurant. The cashier explains to them that the bumper stickers are free to all customers so it would make it hard to narrow it down who it is. The girls order sodas and wait as long as they can to see if anybody suspicious comes in, but the only weird thing that occurs is that the cashier keeps staring at them.
Dawn has been babysitting for Erick & Ryan DeWitt a lot lately & they have a new friend named Timmy Ford. Timmy and his father have just moved in across the street. Timmy’s nice, but really shy, plus he’s having some family issues; his mom isn’t around at the moment and his dad works a lot & they also have some money problems. Timmy doesn’t think that he’ll be allowed to attend the We Love Kids Club Halloween party that’s being held in place of trick or treating. Dawn and the salesperson at the variety store help Timmy put together a costume so he can celebrate Halloween with his new friends. Another robbery occurs on that same day.
On Halloween, Dawn is on her way to a sitting job when she notices the gate to the Fords’ backyard sitting open. As she goes to close it, she notices some footprints in the yard that match the robber’s. At first, Dawn doesn’t think anything of it, but when she passes by the Fords’ garage, she notices the black Chevy Cavalier with a bumper sticker from the hot dog place. Dawn figures out that Timmy’s dad has to be the robber. She rushes across the street to the DeWitts & explains to Mrs. DeWitt what she suspects. They notify the police and Timmy’s dad is taken into custody.
Since the robber has been caught, the parents of Palo City have decided that the kids can go trick-or-treating. Dawn is in charge of taking Clover & Daffodil Austin and Stephie Robertson trick-or-treating. The girls are having fun, but Dawn is a little scared and at one point, she thinks that she sees somebody creeping around through backyards. At first, she thinks that Halloween is getting to her and doesn’t think anything more of it.
But, as they pass the Fords’ house on the way home, Dawn is sure that she sees somebody back there digging wearing an all-black outfit and a clown mask which is exactly what the robber was wearing when Dawn first saw him. She rushes over to the DeWitts and explains to Mrs. DeWitt what’s going on. The police already determined that Mr. Ford wasn’t the robber since he had a solid alibi at the time of the first robbery, so Dawn is curious about who it might be. When the police arrive and they unmask the clown, it is Timmy’s mother (who was the lady at the hot dog place).
In Stoneybrook, the Barretts and the DeWitts are househunting. They find a house in Greenvale, but the kids don't want to leave Stoneybrook, so they find a house that's not too far from the elementary school. Even though it's smaller than the house in Greenvale, the kids would rather have a smaller house in Stoneybrook than have to move.
Halloween is coming, and Dawn and her friends in the We ♥ Kids Club are almost as excited as the kids they baby-sit for. Then, just before the big night, a masked robber holds up a store in Dawn's neighborhood — and Dawn witnesses the getaway!
Even with Dawn's description, the police can't catch the robber, so Palo City's parents set a curfew until the thief is caught.
But that means trick-or-treating is off — and that means a lot of disappointed kids. Unless Dawn and the W♥KC can catch the robber themselves...