Watford reached an agreement to sign Gerard Deulofeu on a permanent basis from Barcelona, both clubs confirmed on Monday afternoon.
The 24-year-old scored one goal and registered a single assist in seven games whilst on loan at the Hornets for the second-half of the season as his nomadic career continued.
The 24-year-old becomes Watford's second summer signing, following the arrival of England youth global Ben Wilmot from Stevenage last month.
"FC Barcelona will also receive a percentage of any future transfer operations to other clubs".
The ex-Barcelona youth player has previously had two spells in the Premier League with Everton.
He was a hit under Roberto Martinez at Goodison Park and, following a loan stint at Sevilla the following term, was signed permanently by the Toffees in summer 2015.
'Our ambition to succeed and grow in the Premier League remains as strong as ever'.
The winger struggled for playing time under Ernesto Valverde, though, making only five starts in La Liga before heading back to England with Watford.
And after impressing at an inconsistent Watford, Javi Gracia has made a decision to snap him up on a permanent deal.