Kal Naismith put pen to paper on a loan deal from Bristol City until the end of the season during the winter transfer window.
The 32-year-old returns to familiar territory having left the Town at the end of the 2021/22 campaign in which he was named player of the season.
The left-sided defender first joined the Hatters in January 2021 and scored his first goal for the club in the come-from-behind 3-2 win over Sheffield Wednesday a month later.
The following campaign saw the Scot make 45 appearances, helping the Town to a sixth-place finish in the Championship – scoring a memorable last-minute winner against Bournemouth.
Naismith – who began his career with Rangers before spells with Accrington, Portsmouth and Wigan – moved to Ashton Gate in the summer of 2022 and has gone on to play 52 times for the Robins.
He was appointed captain by manager Matt Bloomfield in July.