I'm looking for a book I read as a kid in the 80's, I want to say it takes place in a resort in Mexico where a group of Immortals meet including Nefertiti and end up tracked/attacked by the government who wants to capture them and study them so they can make others immortal. I want to say that the main character was a younger immortal, but it's been so long I can't remember for sure if that was right or not. Sadly that's all the details I have but I remember the book having a reddish cover with picture of the famous bust of Nefertiti on it among other things that I just can't remember.
[edit]The book I read was a paperback and was in English, sadly I can't remember any more details about it.