Prank Callers

Synopsis
Mordecai and Rigby decide to make prank phone calls. They try to prank the Master Prank Caller numerous times, although they fail to fool him (and only make him increasingly annoyed). Eventually, he calls Mordecai and Rigby and sends them to 1982. Mordecai and Rigby must then engage in a battle of prank calls against the Master Prank Caller to send them back to the present.

Plot
Mordecai and Rigby are watching a video starring the Master Prank Caller on WooHoo! (a fictional parody of Yahoo!), when they start to pick up the pace and become prank callers themselves. The victims are Pops, Skips, and Benson, always using the term 'Joe Mama' on each call. They attempt to prank the Master Prank Caller himself, but Benson furiously storms in and demolishes the phone as a 'prank'. They instantly decide to use Pops's phone. They find him ironing a shirt, but he is too busy actually taking a call with 'Joe Mama'. Pops allows them to use his 80s phones, but warns them of the possibilities of brain tumors.

Mordecai and Rigby each wrap tinfoil around their heads (to prevent tumors) and call the Master Prank Caller. Mordecai goes first to prank, joking that he had 50 pizzas that the Master Prank Caller 'ordered', but he had actually ordered 50 pizzas along with hot wings that he needed brought over. He quickly hangs up and Rigby goes next. He passes himself off under the psuedonym of 'Stan', but ends up adding 'Standinson' when he is asked for a surname. The MPC warns them to stop calling him, or they would pay. Mordecai and Rigby still attempt to prank him, but to no success. They finally get a call from the MPC, who tells them that he had warned the two, and says, "The 80's called! They want their cell phones back!" to which Mordecai and Rigby are sucked into the phone and transported back to the 80's.

When they are spit out of the phone, they think they are back at the park. Mordecai asks a nearby Pops to "tell Rigby everything's fine", to which he turns revealing his more younger face. Mordecai and Rigby are surprised at Pops's difference and his not knowing of them, and find a couple of B-boys dancing. Rigby tries asking them if they noticed anything strange, only for them to get "barfed out" and leave. It is then Rigby finds out they are in the 80s, more specifically, 1982. They try to call the MPC and apparently send him to the 60s, but the MPC escapes out of the phone (being a literal cell phone with arms and legs) and begins dialing himself. Mordecai and Rigby escape with a golf cart, with the MPC hot on their track. They are called again by the MPC, who says that the 80s still wanted their phones back, to which Mordecai and Rigby are instantly dressed in 80s apparel to their grave horror. They get a second call to which Rigby begs him to leave them alone, only to get dressed in heavier apparel along with Mordecai, whom desperately tells Rigby to call someone who turns out to be Pops, Skips, and Benson in the present time. Rigby explains the situation to Pops, who passes it onto Benson, who hears about the problem. He thinks it's a prank, and from this, all three are transported to 1982 and reappear on the back seat of the golf cart. As they are driving they accidently hit a younger pops ( which probably explains why he is a scatter brain in the present.). The MPC appears right by the five in a limo, even attacking them by running into their side. Skips instructs Mordecai to hold the wheel steady, as he leaps onto the MPC's limo, and later on claims its utter destruction. The MPC breaks out still, as the five run directly into an electronics store. Mordecai hatches a plan using a tape recorder.

Everyone runs back and hides in the bushes as the MPC calls. Mordecai's recording plays, keeping on saying things like, "Hello?" as if no one was there. This angers the MPC, whom reappears and finds out he was pranked. While he cries out, he is ambushed by everyone. Despite his struggles, the MPC cannot break free. Mordecai finally instructs Rigby to hit the power button. Rigby scurries up the MPC and pushes the power button, and the MPC, powerless, falls to the ground. Moments after Mordecai and Rigby celebrate their title, a bright light protrudes from the MPC, which Mordecai claims is the way out.

The five find themselves in a long hallway full of doors leading to certain years. After a while of searching, Benson finally finds the door leading to the present time. The MPC gets their attention, being old and wrinkly. He pleads for Mordecai and Rigby to take him with them, which they accept to do.

In the end, all three prank Benson, transporting the chair he was sitting on back to the 70's.