What is the explanation of the first line of the function secret?

What is the meaning of the first line in the function secret? What is the output of return secret(3,argv)?

#include <stdio.h>
int secret(int argc, char **argv)
{
 *argv && secret(0, argv + 1) &&
 argc == 0 && printf("%s\n", *argv);
 return argc == 0;
}
int main()
{
 char *argv[] = {"hello", "XYZ", "123", "ABC", NULL};

 return (secret(3,argv));
}

>Solution :

This

*argv && secret(0, argv + 1) &&
argc == 0 && printf("%s\n", *argv);

is a tricky (and harder to read, I think) way to write

if ( *argv && secret(0, argv + 1) && argc == 0 ) {
    printf("%s\n", *argv);
}