Damian Scott is sent to Mogadishu, Somalia to rescue British diplomats after they are kidnapped by warlord Huseyin Waabri. Meanwhile Michael Stonebridge adapts to his new career outside Section 20.

Scott learns that one of the hostages is a high-ranking military intelligence operative and that Waabri is planning to sell nuclear devices in South Africa.

Scott and Stonebridge track down a radical Islamic cleric in order to recover the nuclear devices, but are sidetracked by a CIA air strike and hostile locals.

Scott and Stonebridge prepare for an attack by Al Qaeda while holed up in an Algerian farmhouse with the nomad leader and the wounded courier. Meanwhile, back at headquarters, Dalton is called on the carpet for her relationship with the courier.

The trail of the missing nuclear triggers leads to Cape Town, South Africa, where kidnappers abduct the children of an expatriate munitions expert to force him to cooperate.

Stonebridge seeks revenge on Craig Hanson after he turns up in Cape Town, South Africa. Meanwhile, Scott reconnects with a Mossad agent who's been following their case, but with a different set of orders; Knox hustles Evans to a secret installation and explains how he intends to turn his country into a world power.

Knox extricates a political leader from a Zimbabwe prison, and the unit tries to catch up with the escapee by tracking his activist daughter.

Stonebridge ends up being at the heart of a baying mob while holed up in a local prison. Scott attempts to protect Lillian.

The pursued Knox hatches a heinous scheme to unload the nuclear bombs on politically unstable African countries; and Dalton faces down Bryant about the CIA's involvement in Africa. Meanwhile, Matlock comes clean about why he got involved with Knox in the first place.

When Knox strikes a deal with the Nigerian terror group to detonate the nuclear weapons, thereby wiping Johannesburg from the face of the earth, Section 20 race to locate and disarm the bombs before the face of Africa is altered forever.