Complex sentence: LaPaglia was set to return to the role in its sixth season as a recurring character, however in his next appearance in the sixth season premiere "Last Man Standing", he is suspected as a spy within the NCIS and shot by Agent Lee.
Split into simpler sentences: LaPaglia was set to return to the role in its sixth season as a recurring character. He appeared on the sixth season premiere "Last Man Standing" where he is suspected as a spy within the NCIS and shot by Agent Lee.