The episode starts with a cold open, which is in Hal and Lois in bed, while the kids are somewhere outside doing disaster and after some fighting Hal decides to go on to calm them down... for a price.
The episode, with Malcolm being wake up by Reese that hits him because of him they are going to the Krelboyne picnic, later Malcolm tries to do something to not going for the picnic, he tries to fake a vomit but it doesn't works.
Later, the family is in breakfast where Lois argues with Malcolm of why he doesn't wants to go, and when she is not hearing, Malcolm asks for Francis to take him out of the picnic before his turn for the great circus (which is in fact a place where the Krelboynes show their genius abilities) arrives. Francis arranges to take him out in fifteen minutes.
The family arrives to the picnic, where Malcolm is meet by Caroline and his Krelboyne buddies, and later Reese finally decides to kick some Krelboyne butts, while Francis puts his attention on a cute girl that is standing somewhere. Later, Lois and Hal go to say hello to the other parents, but discovers that Dabney's mother doesn't likes Malcolm nor his mother, which cause a battle to start. Hal goes on to cook some meat, and Malcolm tries to help Stevie with his project. Later, Malcolm finds Francis kissing with the cute girl and discovers that they are not, in fact, getting away from there.
Malcolm doesn't wants his turn to arrive, so he tries to make different things to get out, but unfortunately is not enough. Reese chases for some Krelboynes, but it all turns awry where he finds out that one of the Krelboynes has a big brother (who is also a Krelboyne due to the way he dresses and later asking Malcolm what the reciprocal of the credit card numbers are) that instantly chases Reese instead. Lois convinces other women for not being the servants of Dabney's mother that causes some disturbance. Caroline discovers that everything is turning into a disaster, Hal cooking meat causes the Krelboynes to go mad and almost died, and then something happens... Malcolm uses Stevie's experiment and that causes his whole project to explode and then everything in the picnic is in total chaos.
Caroline is being tormented by the other parents, so Malcolm tries to help her, by giving her a hamburger, but it doesn't makes him feel better. So Malcolm asks Francis, that has just break up with the cute girl, if he will still like him if he discover how smart he is. Then Malcolm puts himself up, and begins to show off his math ability, and everyone is impress except for the family.
Finally the family got in the car, where Malcolm thinks that thy will not accept his differences, but later discovers that his family is more comprehensive than what he thought, and they go on to eat some burgers then...