It's about 2 families (the Jones's and the Iqbals). Archie Jones is married to a Black woman much younger than him (Clara). Samad is his (originally from) Bangladeshi friend. The met during WWII, but they're late bloomers. The book (mostly, with the aid of flashbacks) follows their family lives through the 1970s, 1980s and 1990s.
I'm not sure about the book. I found it all slightly depressing. With 1 or 2 exceptions, not a huge amount happens that we haven't seem in other books, and what does, while occasionally funny, left me feeling blah as the book drew to a close.