。
Sounds like an interesting story.
Literal
Interesting-[seems-そうな] story is.
面白そう is the conjectural form of 面白い, formed by replacing い with そう — 'looks/seems X.' This is the speculative/evidential ~そう (distinct from the hearsay ~そうだ). Often used when you see something and form an impression from visual or contextual cues: 'looks interesting.' な attaches it to 話 as a modifier.