I need a great Detective Conan's episode/s Please Help!

[saraha]

Hello, I want to make a mystery murder party in the countryside, but i need a good story, with good backstories of each character (like why did the criminal killed the victim).

I was thinking of making a case of a murder, of a rich old man (victim). With these suspects: wife, mistress, journalist, butler and a coworker/business partner.

The rich man is killed in his birthday party. 

Please help me find a good episode of Detective Conan, i could use or even mix various episodes.

Thank you for giving me part of your precious time!