Paradise
This place has extreme comfort. It is paradise.
ごくらく
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
間違いで極楽に行った男についての小説が、映画化されました。
The novel about a man who went to paradise by mistake was made into a movie.