Relationship status? “It’s complicated.” Spike Jonze’s melancholic tale of romance between a man and a computer-operating system finds the director at his quirkiest. He’s also tapping the zeitgeist as never before. In an era where online privacy and social media dominate the headlines, his musings on the topic feel timely.

Jonze’s not-too-distant future is painted as delicately as his emotional landscapes, with slightly uncanny high-tech cities rendered in dreamily muted colours.

The clothes are unfashionable, the public areas sparsely populated – highlighting the lonely awkwardness of Theodore Twombley (Joaquin Phoenix). An insecure divorcé, his work as love letter writer reveals a deep sensitivity. However, his stilted social interactions betray a fear of intimacy.

When Theodore falls for his Siri-like operating system Samantha (voiced by Scarlett Johansson), these issues of love, technology and projection are brought to the fore. Phoenix’s almost-one-manshow is stunning, while the unseen Johansson has ironically never been better. Like a musician fully in control of her instrument, her vivid vocal performance exudes excitement, sensuality and vulnerability.

In cinemas February 14