Ugly creature concealed beautiful flower (6)
I believe the answer is:
orchid
'beautiful flower' is the definition.
'orchid' can be an answer for 'flower' (orchid is a kind of flower). I am unsure of the 'beautiful' bit.
'ugly creature concealed' is the wordplay.
'ugly creature' becomes 'orc' (I've seen this before).
'concealed' becomes 'hid' ('hide' can be a synonym of 'conceal').
'orc'+'hid'='ORCHID'
Can you help me to learn more?
(Other definitions for orchid that I've seen before include "Much sought-after family of plants" , "Family of flowers with unusual shapes and beautiful colours" , "Varied much prized flower" , "Lush and expensive tropical flower" , "Tropical flowering plant" .)