The episode was written by series one and two head writer Chris Chibnall, directed by Mark Everest and produced by Sophie Fante and Richard Stokes.

The episode featured the five initial series regulars John Barrowman, Eve Myles, Burn Gorman, Naoko Mori and Gareth David Lloyd plus recurring actors Kai Owen and Tom Price.

The episode begins with the alien hunter Gwen Cooper (Eve Myles) being called in to investigate a missing person case by her former colleague in the police Andy Davidson (Tom Price).

When bereaved mother Nikki Bevan (Ruth Jones) starts a support group for missing people, Gwen realises the problem is widespread.

It is revealed that Nikki's son Jonah (Robert Pugh and Oliver Ferriman), like the other missing individuals around Cardiff, was taken by the space-time rift and returned physically and mentally scarred.

Executive producer Russell T Davies appreciated the character dynamics and domestic themes in the episode and cited the script as one of his inspirations in continuing the series.

Reviewers generally praised the episode for illuminating the conflicting elements of Gwen's character and providing a central dilemma with no easy answer.

Gwen collates a chart of the missing people and her colleague Toshiko discovers that all the disappearances occurred during negative spikes of activity from the Cardiff Rift.

Executive producer Russell T Davies felt it provided good drama to have a story that would also examine elements of "paranoia" and "fear" and "mistrust" between Gwen and Jack as result of her realising she does not know the full extent of his work within Torchwood.

[2] Davies later stated in his book The Writer's Tale that "Adrift" was one of the scripts that "paved the way" for the third series of the show; his intention being to write Torchwood characters as "real people" with "families, feuds, aches and pains".

Gwen was initially referred to by her husband's surname, Williams, but Eve Myles vetoed this idea as she believed that an independent professional woman would want to keep her maiden name.

Richard Stokes estimated that the actor had to spend between two and two and a half hours in make-up in addition to a twelve-hour filming day to have prosthetics applied to create the appearance of scarring.

[8] Ian Berriman of SFX rated the episode four and a half stars out of five and felt that it showed "how every SF-related casualty is more than just a statistic – it’s also someone’s life-destroying tragedy".

[10] Ben Rawson-Jones of Digital Spy stated that the script "neatly brings out the conflicting components within Gwen's character" and praised the episode for raising the moral dilemma of whether to reveal the truth or not.

[12] Airlock Alpha's Alan Stanley Blair felt the episode to be a vast improvement on its predecessors stating it be "hard hitting, edgy and explores much bleaker and darker avenues to life in Torchwood".

He also felt that the personal effect of Gwen's struggles on her domestic life was one of the most interesting aspects comparing it to the television series Angel which "touched on some of these threads through the meta-story and vampire mythology" but not "on the scale of this [episode]".

He praised the "tragic emotional impact of the moment when Jonah's mom told Gwen to promise her not to do that to any other families" and stated that he liked "that there weren't any easy answers".