I Need Some Legal Advice - ASAP ??

My friend had his restaurant business (LLC) closed down yesterday by his landlord and forced out. He had bought it from someone (with proof of sale) who was originally on a lease for that space with the landlord. But apparently when he made the sale to my friend he was not on a lease with that landlord. My friend had been dealing only with this middle person and had not signed a lease directly with the landlord but had actually payed the rent for two months to this middle person. The landlord now has eased the property to some other third person and has this forced my friend out of property by force (with police) without any notification. What are the next steps of action he should take legally and who should he file a case against ? Eveything inside the building (including equipement and misc utensils and furniture were fully invested by him) and he needs help to get his investment back. Otherwise he will be broke. Please help.