If you do not want to finish the Story element of the game quickly do not read any further!
There is a quick way to find out who is causing all the things in the Kingdom to disappear and capture the UFO!
After you have got to the part with Mecha dog and have found him in the zoo enter the enpty broken crocodiles cage
In the top right-hand corner there is a strange looking object go to it
You will realise your green sims diamond appear above your character Click on the strange object
You will find yourself in a secret underground lairNow go exploring and watch the WHOLE title sequence at the end!
Congratulations on solving the Mystery of My Sims Kingdom!