Particularly egregious bits are highlighted.
The thing is, I am not pro immigration. I think Britain should have lower immigration (not zero). I'm basically quite communitarian. But what inevitably happens, in the political system we have, is gesture politics where you make some headline number commitment. Then you have to fulfil the commitment. Doing it right would be hard. So instead you do what is easy: you target the most law-abiding, highly visible people because they are the easiest to bully. And then... well, now read on.
Thanks for the support! Yes, I was detained for a pretty long time, and sent back to [first world country Z], but it was largely due to my own stupidity. Although people still seem a bit horrified when I tell the story, so I must inadvertently tell it in a way that understates my stupidity, so keep that potential bias in mind. Here's the full(ish) story. It's pretty long, sorry.
My initial plan was to go to [country X in Africa] for research, and come back about a week before my visa expired and apply for an extension when I got home (which is what you're supposed to do). As is typical, there were some small issues in hiring a staff in X, which caused delays and so I ended up staying longer than I had initially anticipated. In the end I tried coming back into the country 4 days after my visa expired. I was in X, and didn't have time to really research the visa situation, and thought it's not a big deal, I have a Zian passport, I'm allowed to enter for 6 months with a Zian passport without a visa. I really didn't think much of it, I've entered the country without a visa many, many times before I moved over. So, that was very naive of me.
When I got to immigration I was pretty up front and honest about the situation; I didn't think it was going to be a problem. I told the immigration officer that I was gone on research for a month, I lived in the UK, I was putting finishing touches on my dissertation, and would be visiting for 2 months (I have a conference in Z in May). She asked questions about how much cash I had on me, why my visa was expired, and said I couldn't enter to do school work without a student visa. So, alright, I said, I didn't actually have school work left to do, my dissertation is all but complete, I'm really just visiting for a few months while I tie up some loose ends. She thought that it shouldn't take 2 months to do this, and didn't believe that my dissertation was complete since I was gone on research. I tried to explain that the work I was doing was not for my dissertation. She said oh, so you have a job? I said, no, but I expect to get one, and the work I'm doing now will help my career when I get a job. She did not understand my motivation for doing work that I was getting neither course credit nor money for, and basically called me a liar (said it was "highly implausible") and so they sent me to this room/cell thing in the bowels of Heathrow.
I waited there for a few hours, a new immigration officer came and interviewed me, wrote everything down, I told her the same story, I was here for a few months to tie up loose ends with my living situation, and submit my dissertation, and I was leaving the country in May at the latest. She told me there was no way I was going to enter the country, I was clearly doing school work without a student visa (which is kind of true) and they were going to send me to Nairobi because that was where I came from.
I started making calls using my credit card to let people know what was going on: my girlfriend, parents, etc. I had made several purchases on my way back, in Kigali, Bujumbura, Nairobi, and now London. So of course, while trying to make calls, my card got security blocked. My other card had already been blocked for a few days, I hadn't worried about it because the backup worked, but now the backup was down. So this was pretty bad because now I was being sent to Nairobi which isn't the safest place in the world, and I had absolutely no access to cash, not even enough to get a cab to the Zian embassy when I got to Nairobi. This next bit is the worst part I think: I desperately explained the situation to the immigration officer, literally telling her that people regularly die wandering the streets of Nairobi at night, and she said "not my problem, is it?". That was cold. My stomach sank with the lack of empathy. I was basically begging to go back to Z instead of Nairobi. I was pretty scared to go to Nairobi without any money or access to any money.
There was this guy in the cell with me (there were 7 of us) who clearly sensed my fear/desperation. He was a Libyan guy who seemed to know the immigration laws very well. He was there declaring amnesty, and had been detained for almost 48hrs. He overheard the conversation, and mentioned that his understanding was that the law said that I could go to my home country if there was a flight before the next flight back to my destination port, and I paid my way myself. ... So, I called my parents, and got my dads credit card info, bought the last ticket of the day into Z, all on the secretary's cell, and so they let me come to Z....
So, anyway, that's it. I ended up being detained just under 12 hours. I think the worst thing from their end is that they didn't actually ever tell me what my options were under the law. I apparently had the legal right to go back to Z, and despite my desperation and begging to not go to Nairobi, it took some random stranger to tell me that I had the legal right to be sent to my home country. I think it was pretty unreasonable of the officer to just assume that I wouldn't be able to figure out a way to get a flight home. I don't think that was particularly fair treatment.
All in all, not a great travel experience. 2/10 (max) - would not recommend and would not do again.