In 2000, Isaka won the Shincho Mystery Club Prize for his debut novel Ōdyubon no Inori, after which he became a full-time writer.
In 2002, Isaka's novel Lush Life gained much critical acclaim, but it was his Naoki Prize-nominated work Jūryoku Piero (2003) that brought him popular success.
Isaka was the only author in Japan to be nominated for the Hon'ya Taishō in each of the award's first four years, finally winning in 2008 with Remote Control (original Japanese title: Golden Slumber).
His 2010 novel Maria Beetle was adapted as the 2022 major film Bullet Train starring Brad Pitt.
[1] A film adaptation of his 2019 book Seesaw Monster (Shisō Monsutā, シーソーモンスター), starring Anne Hathaway and Salma Hayek (who are also producers), is currently in production and will be distributed by Netflix.