Special Forces World's Toughest Test Season 4 Premieres

Special Forces Worlds Toughest Test returned to Fox on Thursday with a star-studded season filmed in Morocco that threw celebrities into military-style selection exercises designed to push physical, mental and emotional limits. The season 4 premiere, which aired Sept. 25 at 9 p.m. ET, opened with recruits repelling from a helicopter and later requiring teams to haul 800 pounds of supplies uphill in sweltering heat, according to footage and episode descriptions.

The series pits celebrity recruits against a set of grueling challenges overseen by a directing staff of former Special Forces operatives, including Billy Billingham, Jason "Foxy" Fox, Rudy Reyes and Jovon Q. Quarles. Recruits may leave only by voting to withdraw, through medical removal, or by being dismissed by the directing staff, a rule central to the show's selection-style format. Episodes this season will also depict urban warfare simulations such as a rat-run through narrow tunnels, an underwater escape drill and a 50-foot ladder crossing between buildings.

The cast mixes reality stars, athletes and actors. Among those taking part are Kody Brown of Sister Wives; Brittany Cartwright; Teresa Giudice and her daughter...