Plus, in this week’s Installer: a new Mario Tennis, Sony’s great new buds, a wild time-travel movie, and much more.

The toxin was found in the body of the Russian dissident Aleksei A. Navalny, who died in prison two years ago, five governments said, challenging Russia’s official account.

What's your favorite movie that started life as a book — and what makes for a great book-to-film adaptation, anyway? Do you want filmmakers to stay as rigorously true to the book as possible? Or are ...