S4·E4 Leader of the Pack

The past comes back to haunt Richie when he spies Mark Roszca, the street punk who killed Tessa. Richie is determined to go after Roszca and revenge Tessa's death. Meanwhile, MacLeod is distracted by the return of an old Immortal enemy, Kanis -- a master of hounds who uses his pack of dogs to track and exhaust his prey. This time his prey is Duncan MacLeod.