Hi Guys
Please help me to solve this problem
I just debated with my friend as to which is the correct or proper one
between "A LEGENDARY IN THE MAKING" or "A LEGEND IN THE MAKING"

A few hours ago I created a video titled "A LEGENDARY IN THE MAKING"
and then My friend said that these words are grammatically incorrect, She also said that it should be "A LEGEND IN THE MAKING" not LEGENDARY IN THE MAKING

Now please tell me, is it wrong if I Said "A LEGENDARY IN THE MAKING" ??
And Please tell me the difference between these words

Thanks in advance