This is a fairly interesting and semi-informative documentary run-down of the cultivation of the different methods of execution over time. From guillotines, to hanging, to firing squads, to stoning - all featured through actual footage, mostly from third-world cesspools.
"Executions" has a bit more substance than most other "shockumentary" mondo-type-death films, going for a less exploitive take with insightful voice-over narration as opposed to, say, death metal soundtracks or insensitively over-the-top mockery. There's plenty of authentic footage of people being executed, via firing squad and many photographs of beheading aftermath. The end segment, showing one incredibly cruel example of capital punishment will surely bum you out.
If you can handle this type of 'true death' shit, than "Executions" is a decent documentary to check out.