One of my favourite episodes is 'Meeseeks and Destroy'. Rick gives Morty's parents and sister a Meeseeks box in order to help them. Now the way a Meeseeks helps you is you press the button on the box and one appears. You then tell it what you want it to help you with. If you tell it to open a jar, it will open it for you. Then it will immediately stop existing as it has fulfilled it's purpose. In the episode Morty's father decided that he wants to take 2 swings off his golf stroke, as that is a simple task. Long story short it turns out that it's almost impossible for the Meeseek to help him. So the Meeseek uses the box and eventually gets a whole hoard of them to try and help. They all slowly get increasingly angry and frustrated as they can't seem to help him. Thus not fulfilling their purpose and existing MUCH longer then they should. Laughter all around.
"I'm Mr. Meeseeks! Look at me!" Meeseeks catchphrase.
Video clip of the Meeseeks in action!
Honestly I would suggest you all just go and watch the show. there's around 11 episode and they all clock in at around 20 minutes.