Wilmer Valderrama has joined the cast of 'NCIS'.

Wilmer Valderrama

Wilmer Valderrama

The former 'That 70s Show' actor - who recently enjoyed an extended guest starring role on 'Grey's Anatomy' - will appear in the upcoming 14th season of the show as a series regular.

'NCIS' is a procedural TV series, revolving around a fictional team of special agents from the Naval Criminal Investigative Service, investigating crimes involving the U.S. Navy and Marine Corps.

36-year-old Wilmer's character is a "once grounded NCIS field agent who accepted a deep-cover assignment years ago and never resurfaced.

"Many agents don't know he's still on the job or that he's even alive. Now, he's back and his dedication to job and country has left him an unpredictable, charismatic loose cannon."

Executive producer Gary Glasberg in a statement: "Wilmer Valderrama will be able to flex his dramatic, physical and comedic talents in this classic 'NCIS' role. Fans are going to see him like they've never seen him before. This is going to be fun. We're thrilled he's coming aboard."

'NCIS' stars Mark Harmon, Pauley Perrette, Sean Murray, Rocky Carroll, Emily Wickersham, Brian Dietzen and David McCallum while fan favourite Michael Weatherly left at the end of season 13.

While Wilmer's professional life is going from strength to strength, he has not been so lucky in his personal life, recently announcing the end of his six-year relationship with Demi Lovato, 23.

They said in a joint statement: "After almost 6 loving and wonderful years together, we have decided to end our relationship. This was an incredibly difficult decision for both of us, but we have realized more than anything that we are better as best friends (sic)."