Complex sentence: He rejoined the Drifters, now with four new members, and became the lead singer in 1964, after the death of Rudy Lewis, who was due to record "Under the Boardwalk" the next day, and Moore took over the lead vocals.
Split into simpler sentences: He rejoined the Drifters, now with four new members, and became the lead singer in 1964, after the death of Rudy Lewis. The group was due to record "Under the Boardwalk", and Moore took over the lead vocals.