In my experience, companies, even/especially large international companies can do whatever the hell they want, and you have little comeback.
If your boss takes away your car, then you can try whatever you want - you won't get your car back.
You can leave, and claim constructive dismissal, go to court, and win - but all you'll get out of it is the statutory minimum amount that you would have got had you been made redundant. And, it'll make your future job search more difficult - you'll be branded (rightly or not) as a troublemaker.
I don't agree with BM's opinion of unions - one thing (possibly the only thing) that unions do give you is unparalleled legal support - the best employment lawyers get their bread and butter from unions.
The best thing you can do is use this opportunity to get out, get a better job, a more satisfying life, and (in the fullness of time) tell your current boss to shove it.