In this series Professor Iain Stewart tells a stunning new story about our planet. He reveals how the greatest changes to the Earth have been driven, above all, by plants. In this first episode Iain journeys from the spectacular caves of Vietnam to the remote deserts of Africa. He sees how plants first harnessed light from the sun and created our life-giving atmosphere. He uncovers the epic battle between the dinosaurs and the tallest trees on the planet. And, using remarkable imagery, he shows plants breathing - and for the first time talking to each other.

American troops launch widespread 'search and destroy' operations; body count, not territory, becomes the measure of success in Vietnam. Charles Brown fights for survival on the bloody slopes of Hill 875 and at home, the American public begins to question U.S. military strategy.

Vintage footage from the Vietnam war is presented along with narration from both war veterans and Hollywood voice talent. The documentary follows key events and their impact on both the war effort and the American public.
The Beginning: The first episode looks at the early months of the Vietnam war from the escalation following the Gulf of Tonkin incident to the grim fighting of the Battle of Ia Drang where a few hundred American soldiers are pinned down by three battalions of North Vietnamese infantry. Using superior air power and reinforcements, the Americans fight the North Vietnamese to a draw.

The enemy gains ground when the massive Tet Offensive catches the Americans by surprise. At Khe Sanh and Pleiku, U.S. troops are under siege. Americans mount a counteroffensive but the shock of the assault ignites anti-war fervour at home.

The turmoil of 1968 helps Nixon win the presidency. Troop strength in Vietnam peaks and the draft accelerates. Karl Marlantes endures bitter jungle fighting on Hill 484, and draftee Arthur Wiknik gets a grim introduction to combat on 'Hamburger Hill'. But shortly after winning both hills, US troops abandon them.

Troop withdrawals begin as the Americans train their ARVN allies to take over the war. Gery Benedetti patrols the hostile waters of the Mekong Delta. James Anderson leads a battalion into Cambodia after Nixon's controversial order. Don DeVore struggles to survive a fierce night attack, and Anne Purcell gets promising news about her husband.