What is the plot?

In Pikmin 1, Captain Olimar from planet hocotate, crashes on PNF-404, and he has to use the Pikmin to collect 30 ship parts, in 30 days, since his air supply will only last 30 days. Depending on how many parts are collected, the ending changes. If the player collects 25-30, Olimar escapes. If the player collects less than 25, Olimar crashes once again, and the Pikmin transform him into a Pikmin to revive him.

In Pikmin 2, which is the sequel to the good ending of Pikmin 1, Olimar returns home, but before he can see his family, the president of Hocotate Freight (the compnay Olimar works for) tells him that they are in huge debt, since the new employee Louie supposedly got a shipment of golden pikpik carrots eaten by a space bunny. So Olimar and Louie are sent back to PNF-404 to collect treasure to repay the huge debt.

After "beating" Pikmin 2, Olimar realizes Louie was left behind on the planet. So Olimar returns ot PNF-404 to save Louie, but this time, the President joins. At the end of the final cave, the Dream Den, where they find Louie supponsedly unconcious on a dangerous spider. However, after "rescuing" Louie, it is revealed that he was controlling the beast all along, leaving his morality questionable. After that, Pikmin 2 ends.

Pikmin 3, unlike Pikmin 1 & Pikmin 2, does not focus on Olimar, and instead focuses on three new characters from planet Koppai, Alph, Brittany and Charlie. Due to a booming population, booming appetite and a basic lack of planning, Koppai has a food shortage. The trio of Koppai heroes are sent to PNF-404, to collect food to save their planet. On the way, they meet and Rescue Olimar and Louie, who once again were sent to repay a huge debt, but once again crashed.(presidents fault lol)

Pikmin 4, the newest game is the series, focuses on the Rescue corps, a rescue team. Olimar ONCE AGAIN crashes on PNF-404 and sends out a SOS signal. The rescue corps deployes a new recruit (You) to save Olimar, but you have a cute dog Oatchi to help you. However, the mission is not as simple as it seems. Olimar, met a terrible fate, simillar to the bad ending of Pikmin 1. Thankfully, you cure Olimar and everything is good, Right? Oatchi becomes infected, and you must return to PNF-404 to cure him. The only way would to find a stranded vet, but Louie has captured her, further showing how Louie is not as innocent as he seems. The vet is saved, and with the help of cells from another dog, Oatchi is cured.

In Hey! Pikmin, Olimar crashes his S.S Dolphin II on a new planet that somehow also has Pikmin. He loses all his fuel, so he needs to collect treasure so he can use their sparklium to fuel his ship. He collects the sparklium with the help of the Pikmin types from Pikmin 3, and after collecting 30,000 Sparklium, his ship is fixed and he flies back to Hocotate.