Need some legal advice

Hi, myself and the Spikecofilms have been secretly planig a series about mcdonalds Called "Behind the Golden Arches" Now this story will be a humourous documentary that will make fun of mcdonalds. Upon telling my parents about it they told me there is possibility of lawsuits against myself and my team, now first off i would take all the lawsuits to myself if so it happened to protect the others, but do you think it is possible, The film will make no money, but will distictivly make fun of them, and possibily humiliate them with some true/untrue fact. Any information you can give will be greatly accepted.

EDIT: 'm really anxious to do this film, this idea was originally made up by Benbrickstudios for the team, but we dont want to go through if we'll be taking heavy fire, though i really wouldnt mind a lawsuit from mcdonalds, it would get some great publicity for brickfilms, and i would probably win if i'm thinking right... :twisted:

Thanks,
Chris and the Spikecofilms team.