Keanu ReevesKeanu ReevesKeanu Reeves is not a big advocate of the saying 'life begins at 40'.

Instead The Matrix star has revealed that starting his fifth decade last year plunged him into a period of depression.

According to Female First, the Hollywood actor felt enormously gloomy when he started to brood about how many years he had left on the planet.

"It was a nightmare," he admits. "It reminded me of adolescence and it felt like an internal transformation with physical aspect, like when your hormones run wild.

"But this time with a conscious shift, an awareness of your own mortality."

The Canadian-born actor hit 40 on September 2nd 2004.