Complex sentence: Moore and Ridgen returned to Mississippi every few months to continue filming, making nine trips in total for "Mississippi Cold Case"; each time they visited Dunn Lampton, where Moore presented more of the data they had found.
Split into simpler sentences: Moore and Ridgen returned to Mississippi every few months to continue filming, making nine trips in total. Each time they visited Dunn Lampton, where Moore presented more of the data they had found.