English and Norwegian speaking Menkin, who was revealed to be the US voice of Jack, is to voice Virgil Tracy in the forthcoming revival of the late Gerry Anderson produced series.
Meanwhile, Gallagher announced on Twitter that she was cast in the program, just a day after actress Rosamund Pike of Wrath of the Titans and recent The World's End fame, was confirmed by the press to play Lady Penelope.
Not being famous & last to be cast, am not featured in [yesterday's] Thunderbird news items, but am THRILLED to say yes, yes I AM in [the] cast of new TB!!
Fellow Thomas cast member, Kerry Shale then tweeted Gallagher in support; Big Congrats, Tree. Am hoping for a guest villain spot!
Original voice artist David Graham is to reprise his role as Parker, Penelope's chauffeur while Facejacker and Four Lions star Kayvan Novak will portray Brains.
Thomas Brodie-Sangster and Rasmus Hardiker take on the Tracy brothers Gordon, John and Alan and Scott respectively.
The CGI and live-action project is to be directed by The Lord of the Rings and Superman Returns' visual effects artist, David Scott.
Thunderbirds Are Go! is coming soon to UK television on ITV in 2015.