2 Section are sent to Nepal on a humanitarian mission after a devastating earthquake hits the region. They have their hands full distributing aid and tending the injured and then an aftershock hits.

Maisie takes a risk to rescue Georgie and Milan from the collapsing house. When they discover that children from the village have been taken to be sold as slaves in Kathmandu they set off to free them.

2 Section are sent into the heart of Afghanistan on a covert mission to raid the compound of Aatan Omar. The mission gets off to a bad start and gets worse as the section take casualties.

An exhausted 2 Section retreat to Kabul in a commandeered vehicle in a sandstorm. However, instead of returning to Nepal they must support a final attempt to capture Omar.

Still grieving and heartbroken from the death of Elvis Harte, Lance Corporal Georgie Lane (Michelle Keegan) is sent to Nigeria on a training mission, alongside 2-section. Working as part of the British Army's effort to help train local forces in the fight against terror, Georgie throws herself into work helping to train local medics, as well as overseeing a local women's health initiative. However, whilst 2-section work hard helping to equip the Nigerian Army, everyone is soon put on edge when they encounter a local crime boss and a seemingly ruthless band of ...

Georgie can do little as the Boko Haram rebels beat the Nigerian members of the group. She finds the unlikeliest of allies when the local crime boss is revealed to be an undercover special forces operative.

Now in Belize for a jungle training exercise Section 2 members quickly get into a row with natives at a bar. Split into two teams by local commander Mendez the aim is to locate and return to base a mythical injury victim. James' group beats Georgie's but he is shot in the leg by drug-dealing bandits and Georgie, helped by local boy Ezra, attempts to bring him back to safety, discovering a truth from him as they try to escape from the drug-dealers.

Back at base the section receives a weak signal from James' tracker and Bones arrives with his team to locate him and Georgie. The endangered couple are helped by Ezra, who takes them to the safety of a cave, where James admits to a responsibility for the death of Elvis. The pair are rescued but not without innocent casualties.