Somerset have signed big-hitting Ireland all-rounder Kevin O'Brien for five of their Friends Life t20 matches, starting with Wednesday's opener against Warwickshire.
The 28-year-old, who famously scored the fastest century in World Cup history last year when he made three figures off only 50 balls in Ireland's shock victory over England, played for Gloucestershire in last season's FLt20 competition.
Somerset director of cricket Brian Rose said on his club's website: "Kevin is a very attractive batsman who can score his runs very quickly and will add to our already exciting batting line up."
He added: "He will join overseas players Richard Levi and Albie Morkel in the team to face Warwickshire in our opening FLt20 game on Wednesday."
Somerset have finished runners-up in the last two FLt20 campaigns, losing to Hampshire in the 2010 final and then against Leicestershire last year.