The River Rats originated in Frome in 2023 as a classic rock band with Phil Howard on bass guitar and featuring a male lead singer. A keyboard player was needed to be able to play a full and varied repertoire. The search for a keyboard player resulted in Eva Klos from Bristol joining in early 2024. The existing line up was completed in June 2024, when Kirsty Hayes  joined the band as lead singer. The inclusion of keyboards and a female singer changed the dynamics of the band to allow a wider range of musical styles and the opportunity to interpret some songs traditionally featuring male vocals with a female singer.