I'll just bluntly put it at the very beginning to save your time.
The Deep State is nothing but the British Monarchy which still controls most countries of the world, including the so called 'superpowers'. The British Empire (as well as other visible colonial powers) only pretended to decolonize after World War II, as they had planned. Since then they have pretended to be weak and stayed almost hidden, but at the same time they developed very powerful and covert weapons and control technologies, some even believed to involve advanced concepts like hyperspace, nanotechnology, genetics, cell organelle biology, epidemics, directed energy, biometrics ranging from visible features to energy signatures of people, total digital surveillance and control, global weather control, brain/mind control, transhumanism, etc. To easily push all this without organized opposition, they have regained increasing control of previously colonized places and conquered places in powerful and secret ways. These powerful and secret ways include hijack of governments, institutions and economies, as well as control of people. Again, the control of people is both at mass level and individual level. As of today they control nearly the entire world including the visible biggest baddest superpower USA, and most leaders and prominent people around the world. But their control is meant to be extended even more strongly to every individual person.
While staying hidden they are working to turn their hidden global Empire into a 'Satanic' New World Order (NWO), enabled by the powerful and stealthy technologies and other means they now possess. This is intended to happen with or without an official World War 3, but the transition definitely involves killing a large number of people like Thanos did in the movie Infinity War or like Daenerys Targaryen killed a large number of civilians after conquest of seven kingdoms, even though the enemy military had already surrendered.
Through this transformation and massive depopulation into a New World Order, they want to consolidate their final unshakeable, undefeatable power over the whole Earth, even on regions they do not exert very strong control over right now. Then begins an endless rule of extreme selfishness, falsehood, injustice, death, tyranny and slavery, executed through high technology from Earth as well as from space, while the real evil top bosses who control it all stay well-hidden in perpetuity. Many of these technologies are so powerful and stealthy, so pervasive and omnipresent, and produce effects so much beyond most people's common sense and impression of current science and technology that they are likely to bring back or strengthen belief in religion, superstition, god, paranormal and such things or maybe even in extra-terrestrial aliens. They can even create observations that seem to defy known science, propagate pseudoscience. In this way, the understanding of science and technology among common people may also die, and thus kill the last hopes of understanding and fighting back the tech dystopia New World Order.
The British Monarchy is not alone but rather at the top of Deep State hierarchy, calling the shots. Elizabeth II is of course the current British Monarch and the global Empire/NWO is being consolidated for Prince William (the primary successor after his father Prince Charles) and his brother Prince Harry. With them are other royal, feudal, colonial & corporate families lower down the pecking order who are planners, perpetrators and beneficiaries of the same evil agenda and typically have bloodline or marriage or traditional servitude relations with the British Monarchy over centuries.
So we, the common people of the world have a small window to recognize the existence of Deep State, recognize its people, free the governments of our countries from its clutches, stop its 'Satanic' New World Order agenda, save our necks, and have a chance at good life for us and our successive generations. For this, not only must we recognize and fight the people of Deep State, but more importantly, we must also recognize and fight the principles by which they operate. Then we must replace or modify those principles in ways that benefit us all rather than benefit only them by exploitation and deaths of the rest of us. Otherwise even if we manage to defeat those currently at the top, same or similar machinery will be run by someone else down the hierarchy, either visibly or invisibly.
Of course if I start writing on all this, I'd keep on writing and investigating and writing to fill endless books because the Empire itself has worked in big complex ways through a big complex history, and now it has big complex technologies for its big complex plans of ruling the whole Earth and then the galaxy. So I'll stop with this limited introduction using your limited time. If it captured your interest, read the rest of the things I will keep writing on this topic. Subscribe and share widely. If it did not capture your interest that much, even then I still managed to convey the crucial things that you needed to know. Then as events in real world unfold, you will recognize the truth of what I say, and maybe you can come back and read, hopefully still in time to stop the 'Satanic' New World Order. Some or all parts of this quick and blunt introduction may seem far fetched but it is all true. Providing detailed evidence of various aspects of this complex machinery would of course need a lot more writing than this initial article.