Dolph and Scott have worked on several movies together previously including The Expendables 2, Legendary and Universal Soldier: Day of Reckoning.
Word is, Dolph is currently undergoing knife training as 4 Towers will have some epic knife fights.
SYNOPSIS: A Serbian ex war hero, Viro, (Dolph Lundgren), takes hostages at a powerful company’s dinner in an 11th century castle in a bid to capture the legendary stolen gold of Mussolini. Taking on Italy’s tactical swat teams and an Interpol unit (Scott Adkins and Gianni Capaldi), he may have captured a hostage who could prove too much to handle. Intense combat, thrilling knife fighting and explosive action follows Viro as he attempts to escape with the cursed gold and treasure.