The 27-year-old came through the ranks at Bristol Rovers, starring for their successful academy side before joining Premier League Arsenal for a compensation fee in October 2013.
Following a brief loan spell with Accrington Stanley, he gained experience at the Emirates Stadium with Arsene Wenger’s squad, providing cover for Petr Cech and David Ospina during Premier League and Champions League matches.
On January transfer deadline day in 2017, Macey joined the Hatters on loan and went on to make 13 appearances during his time at Kenilworth Road, keeping four clean sheets.
He was recalled early by Arsenal to provide depth once again, before making his Gunners debut in the Carabao Cup in the October, followed by his Europa League debut nine days later where he kept a clean sheet against Red Star Belgrade.
The 6ft 7in stopper joined Plymouth Argyle for a season-long loan in League One in the 2018-19 season, before moving away from London permanently to join Scottish Premiership side Hibernian in January 2021, helping Hibs to a Scottish FA Cup final and a third-place finish to qualify for Europe.
Last season he made 43 appearances in all competitions and kept 14 clean sheets, but has chosen to return south of the border to sign for the Hatters for a second time.
The Bath-born keeper said: “I’m really excited. When I heard there was some interest I was desperate to come back. I had such a good time here, even though it was very brief last time.
“When I came here five or six years ago, I was probably still a boy. I was still learning and I’d only played four or five professional men’s games before I made my debut here.
“I’m coming back with over 100 games under my belt, big experiences in big games and atmospheres in Scotland, and I feel like I’ve grown as a person and a player from that.
“It’s brought back a lot of memories today. I had a lot of fun in that ten-week spell and I look forward to starting again.”
Manager Nathan Jones currently has James Shea and Harry Isted in the senior goalkeeping department, with the former facing a lengthy rehabilitation period following his recent knee operation.
After adding Macey, the Welshman said: “We know Matt, so we’re delighted to get him in. He was excellent for us in our League Two campaign before he was recalled.
“We really wanted to strengthen the goalkeeping department and this year we didn’t want to be in same position as we’ve been in previous years, having to take emergency loans.
“We’ve made the decision to sign two established keepers, along with Harry and Sheasy, but two that are young enough to work with and develop.
“We brought in Kevin Pilkington to strengthen the goalkeeping department, and we wanted to follow that up by signing players to further strengthen it. Matt is part of that.
“He has good experience, but he’s nowhere near his ceiling and one we’re excited to work with again.”