THE MERCY (12A, 102 mins) Drama/Romance. Colin Firth, Rachel Weisz, David Thewlis, Kit Connor, Finn Elliot, Eleanor Stagg, Jonathan Bailey, Ken Stott, Simon McBurney. Director: James Marsh.

Released: February 9 (UK & Ireland)

Fifty years after the Sunday Times launched the Golden Globe Race - offering a £5,000 prize for the first sailor to single-handedly navigate the world non-stop - the fate of one entrant is still anchored in uncharted waters.

Amateur yachtsman Donald Crowhurst set sail on October 31 1968 in an unfinished triple-hulled yacht laden with untested, newfangled gizmos.

He provided updates on his progress via radio and caught the public imagination by taming stormy seas and gaining ground on more experienced competitors.

Unfortunately, his heroics were a web of lies.

Crowhurst was stranded in the Atlantic in a stricken vessel while falsified logs suggested he was making excellent headway and rounding Cape Horn.

On July 10 1969, his boat was discovered in the Atlantic without any sign of its captain.

Authorities presumed Crowhurst had committed suicide because he could no longer maintain the facade of his false voyage.

His body has never been recovered.

The Mercy is a handsome but emotionally waterlogged dramatisation of this fateful journey of self-discovery, directed by James Marsh, who captained The Theory Of Everything to Bafta and Oscar glory.

Romance also bubbles to the surface of Scott Z Burns's script but there are noticeable leaks when it comes to visualising the deterioration of Crowhurst's mental state in the claustrophobic confines of the yacht.

Donald (Colin Firth) attends a 1968 trade show with his sons Roger (Kit Connor) and James (Finn Elliot) to sell their invention: a nautical navigation device.

The family's pitch is interrupted by a rousing speech from pioneering sailor Sir Francis Chichester (Simon McBurney), to launch the Golden Globe Race.

Donald has always been a dreamer and he informs his wife Clare (Rachel Weisz) that he intends to take up the mantle, quoting one of his idols, Sir Edmund Hillary.

"Men do not decide to become extraordinary, they decide to accomplish extraordinary things," he eulogises to his proud sons and daughter Rachel (Eleanor Stagg).

Buoyed by investment from local businessman Stanley Best (Ken Stott), Donald begins construction of a revolutionary triple-hulled yacht christened the Teignmouth Electron.

Media publicist Rodney Hallworth (David Thewlis) and assistant Wheeler (Jonathan Bailey) are drawn to Donald's underdog story, attempting the impossible against seasoned sailors like Robin Knox-Johnston.

They are suckered just like the public.

The Mercy struggles to keep a real-life tragedy afloat.

A ramshackle script bobs between present and past, inserting flashbacks to happier times in Donald and Clare's relationship as his sanity unravels.

Weisz is stranded on dry land and off screen for extended periods, so she fails to make a significant impact.

Being lost at sea with Firth would be a dream vacation for some people and the Oscar-winner delivers a committed performance.

However, I struggled to tether an emotional connection to his tormented sailor and my interest went overboard before Crowhurst contemplates a shame-fuelled sacrificial plunge.

:: SWEARING :: NO SEX :: VIOLENCE :: RATING: 5/10