My boyfriend's gmail got hacked? how can i get it back?

I know 4 sure it wasnt hacked bcuz he told me and i chatted with the hacker and he wasnt acting like my bf and he couldn't answer out "secret question." we are concerned about the safety of his account i know who hacked it and i have proof is there any website that i can report him to? (free and easy 2 use.) i was thinking of pulling a prank on him, make him think that im calling the FBI on him and make him tink im phyco and then scare him out of hacking it or ever hacking it again. but then again, he got in trouble with utube for boiling a live cat in his boxers (nasty.) and he can hack any account in an instant. hes always bothering me to ya know... do IT with him [i REFUSED] and hitting on me (yes im dead serious when i say this but, he went to a crazy house before.) and idk what to do now.
My boyfriend's gmail got hacked? how can i get it back?
I would not bother messing with him or the account that he hacked. Open a new account and use a good strong password for it. Once you do that, make absolutely sure you do NOT give out that information to anyone, ever.