This one has some Giallo elements (the title with the colour in it, a mysterious murder, loads of style) but may well be one of them spy-thriller type things too (I know nothing about that genre). I'll tell you one thing, though - it's a bit of patience-stretcher even though it's gorgeous looking.
A woman reports her husband missing while on holiday in Rome while a tramp finds a corpse propped up at the Trevi Fountain. A handsome American reporter gets involved with both cases (especially as the woman is his ex!) and starts to find links between them. Meanwhile, two burglars find they've burgled an already ransacked flat but find a strange package in the heel of a shoe. Also there's a fat guy going around spying on folks and there's a cop with a bad stomach also on the case. And the mafia too - I forgot about them. And a hooker. And another one of the reporter's ex-girlfriends. And another one of them too. And an ex-drug addict painter.
The woman lists all the people she knows in Rome: a strange couple and an even stranger old man who kept pestering her husband. After a flashback at the Coliseum, and a visit to the Cinecitta (where an extremely camp man comes onto our reporter!), everyone heads off to Venice to catch up with the mystery there.
As I said, this is a very fine looking film and not too bad a mystery, but considering the other films surrounding it chronologically it could have used a bit more bite, and probably a better explanation (more than "So THAT's who it was"). I still have no idea who the fat guy was in relation to anything else, and he tried to kill the hero about ten times! Maybe I wasn't listening. There are a few twists in here that are pretty good, and the death of the killer turns up in Argento's Cat O Nine Tails (and I'm gonna come right out and say it, a lot of stuff from these early films turns up in Argento's films, but who cares?).
I wish they wouldn't smoke so much in these films. I used to love smoking in Rome - nothing better than a 'Diana' or an 'L&M' on a veranda at night listening to all them cars beeping at each other. Best way to end a hard day's sightseeing and eating. I used to always hit my head of the shutters on the way back in because I was too stupid to lift them up high enough. Now it's caravans in Flamborough and weak lager and fresh air.