Vice-champion of Scotland strengthened by two players from the Premier League.
Goalkeeper Joe Hart and midfielder James McCarthy will play for Celtic, the Scottish club's official website said..
The 34-year-old ex-Tottenham goalkeeper signed a 3-year contract with the Celts, and the 30-year-old midfielder, who left Crystal Palace at the end of the 2020/21 season, entered into a 4-year agreement.
Hart, who has 75 caps for the England national team, has played for Shrewsbury (58 appearances in all competitions), Manchester City (348), Tranmere Rovers (6), Blackpool (5), Birmingham (41), Torino (37),.
McCarthy has 43 appearances (0 goals) for the Irish national team. At club level, James played for Hamilton (110 appearances in all competitions, 15 goals), Wigan (133, 8), Everton (133, 6) and Crystal Palace (52, 0).