Watch: Trailer for Line of Duty series 6
When the sixth series of Line of Duty begins this weekend, one of the millions of people glued to the TV will be Henry Winkler, aka The Fonz from Happy Days.
In an interview with Cosmopolitan to mark the crime show's return, star Vicky McClure was asked to name the most surprising celebrity fan to emerge, and recalled that Winkler had got in touch.
"We did have The Fonz, aka Henry Winkler, tweet us that he's a fan of the show which was the biggest moment for us all." she said.
"He's the biggest man on earth. It's gone stateside. And who's cooler than The Fonz? So that's always stuck with me."
Winkler did indeed reveal his love for Line of Duty in a tweet last year, placing it alongside Bill Hader's dark comedy Barry and police procedural Spiral in his list of binge watch recommendations.
Line of Duty returns for its sixth series this weekend, following the continued exploits of the AC-12 unit as they attempt to uncover corruption within the police force.
McClure portrays undercover officer DC Kate Fleming, with Martin Compston as her partner DS Steve Arnott and Adrian Dunbar as the unit's boss Superintendent Ted Hastings.
Read more: Previewing Line of Duty series 6
The show is consistently among the highest performers for BBC in the ratings and has attracted critical acclaim, as well as dozens of awards nominations and multiple wins.
Series six will feature seven episodes rather than the usual six and is due to introduce Kelly Macdonald to the cast as DCI Joanne Davidson
Over the history of the show, many of the most famous faces in the British acting world have appeared, including Thandie Newton, Stephen Graham, Keeley Hawes and Daniel Mays.
Many of those actors — including Mays in 2017, Hawes in 2015 and Newton in 2018 — were nominated for BAFTAs for their work on the show.
Few would likely quibble if Winkler were to join the list of guest stars — American accent or not.
Line of Duty series six begins airing on BBC One from 21 March.
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