"Here you have a trivially simple method of injecting legit-looking messages into text conversations with anyone, providing you know how your target stores the spoofee sender in their contacts. In the UK, that’s largely the difference between starting with 07, and +447.
The utterly exquisite reality is that, if your target then replies, that reply goes to the real sender, who is overwhelmingly likely to reply something like “what the hell are you on about?”, this being the first they’ve heard of this shady business. Does that look like backtracking or denial? I ain’t no Member of Parliament, but it sure sounds like it to me."