If by series you mean anime - it is best wishes black & White & it is in the Unova. Ash meets iris & axew & does his usual adventures with his friends meets up with cilon after the first gym. Jessie & James & meowth are alot more serious & look like spys...
If you mean the game- you pick your starter out of the usual grass/fire/water types catch the new pokemon until you beat the league beating the gyms as usual. You have 2 rivals here - one wiu your stronger pokemon with the type advantage to your pokemon (Cheren) & the pokemon with the disadvantage type to yours (bianca) & you meet n & have to stop him & team plasma ect.
If you mean manga- I have no idea but serebii might.
For mor info on each, go to serebii, they have alot of information on each.
Hope this helps :)