In the fourth episode, Dromaeosaurs stalk a hadrosaur herd as they cross a freezing river. Male Ornithomimus raid rival nests to bolster their own. Olorotitan raise their offspring on fertile volcanic fields but contend with biting mosquitoes.
Troodontids hunt mammals flushed out by a forest fire. A juvenile Antarctopelta scours the forest for a new winter den. Within the snow-covered forest, a tense standoff develops between ancient rivals, Pachyrhinosaurus and Nanuqsaurus.

In the last episode, Austroposeidon level trees in search of fresh foliage. A herd of Triceratops journey through a cave to find an underground clay lick. A male Carnotaurus sets the stage for an extravagant display. A female Qianzhousaurus uses an autumn storm to her advantage while hunting Corythoraptor.
A family of Edmontosaurus evade a forest fire, while an Atrociraptor and Ankylosaur reap its rewards. Juvenile Therizinosaurus attempt to climb up to a bee nest. Hatzegopteryx hunts Zalmoxes, and patrols the dense undergrowth and seaspray-battered coastline.

In this mind-bending series, Professor Jim Al-Khalili explores the vast range of size in the universe, from tiny atoms to gigantic, interconnected galaxies.
In the first episode, Jim will enter the world of objects that are too tiny to glimpse with the naked eye. Starting with the smallest insects, he moves on to encounter living cells with amazing superpowers and confronts some of humanity's deadliest enemies in the form of viruses. Going smaller still, he encounters wondrous new nanomaterials such as graphene, discovered by physicist Andre Geim. These are revolutionising engineering, medicine, computing, electronics and environmental science. Finally, Jim comes face to face with the fundamental building blocks of the world around us – atoms – and reveals why understanding the science of the 'small' is crucial to the future of humanity.

In the concluding episode of the series, Jim encounters ever larger cosmic structures to reveal the latest breakthroughs in our understanding of the universe. For example, Jim comes face to face with our galactic home, the Milky Way, a monstrous structure sculpted by the gravitational forces of dark matter. Jim finds out from pioneering researcher Adrian Fabian about the black hole at its centre, whose strange behaviour includes emitting the lowest note that can be heard in the cosmos.
At an even greater scale, Jim encounters huge structures such as the Laniakea Supercluster, of which the Milky Way is only a tiny part. Then there’s the 'Giant Arc', a collection of galaxies that account for more than three per cent of the observable universe. Jim learns from its discoverer, British PhD student Alexia Lopez, that this gargantuan structure is forcing scientists to reassess their theory of how the universe evolves and may overturn some of the most fundamental principles in physics.

In 2011, a Social Security lawyer named Eric C. Conn and a judge named David Daugherty were investigated for committing massive fraud over many years. Conn figured out that he would get paid a hefty retainer for every Social Security disability payment he managed to get approved, so he and Daugherty (who need quick cash to pay for his daughter’s upcoming narcotics trial – which presumably meant bribing an awful lot of people) came to an arrangement.
In the second episode, Investigators starts to collect evidence against Eric and Judge Daugherty. The whistle-blowers are pressured.

Eric C. Conn became a local celebrity and maybe even became heroic in the eyes of the people they were helping. He put up billboards all over the county and his parties were legendary. Conn took monthly vacations to exotic locations as a sex tourist and his 16 marriages were the talk of the town.
In the third episode, a new U.S. attorney begins working the case. Things take a dark turn when several of Conn's former clients share their experiences. Wanted by the FBI, chased by the authorities, the story soon spirals into a twisty-turny thriller. That’s no coincidence either, given Conn mentions numerous times that he likens himself to James Bond. James Bond with a dash of Robin Hood.