It's not a Japanese film though. I watched Hot Fuzz (or to give its Japanese title ホット・ファズ -俺たちスーパーポリスメン! "Hot Fuzz: We Are The Super-Policemen!")
Watching dubbed British comedies might not be the "purest" way to practise Japanese. But if you enjoy it, it's definitely worth doing. Dubbed films are easy to watch, too, assuming you've seen the film before and know the plot already.
Anyway, there's a little scene in the Hotto Fazzu dub that's a nice example of Japanese plurals in action, so I thought I'd share it with you.
Angel and Danny are in the corner shop, and the shopkeeper asks them:
satsujinhan tachi tsukamaranai no?
"No luck catching them killers then?"
"Killers" is translated as 殺人犯たち satsujinhan-tachi.
You take the word 殺人犯 satsujinhan (murderer) and add the suffix たち tachi - which makes it plural.
See? Japanese does have plurals! ...when it needs them.
Danny doesn't notice the shopkeeper's slip-up (she knows more than she's letting on), and replies:
hitori shika inai n da kedo.
"It's just the one killer actually."
PC Angel, of course, mulls over the shopkeeper's words, and realises their significance: there's more than one killer on the loose.
It's the turning point of the movie, and it rests on a plural. Yay!
You can use たち like this when you need to indicate plurality:
私たち watashi-tachi we, us (plural)
あなたたち anata-tachi you (plural)
ジョンたち jon-tachi John and his mates