S06E35: Wally's Practical Joke

Wally and Eddie fall prey to Lumpy's practical joking after he plants cherry bombs under the hoods of Eddie's car and Wally's car. Both Eddie and Wally want to get him back but their plan goes awry when they destroy Lumpy's car after chaining it to a tree. All fingers point to Wally after Fred finds that the chain has Ward's name printed on it.