Death Valley fans said the same thing as they were left distracted minutes into the latest episode on Sunday (June 1).
The six-part murder mystery series premiered last weekend, and centres around a retired actor called John Chapel (Timothy Spall).
During the opening moments of the show, John's neighbour gets murdered unexpectedly, leading to him teaming up with DS Janie Mallowan (Gwyneth Keyworth) to find the identity of the culprit.
The unlikely crime-solving duo get to the bottom of gripping murders each week, with various stunning Welsh locations providing the backdrop to their investigations.
During tonight's episode, Janie received a call from her mum, Yvonne, while she was out with her walking group.
Yvonne revealed that one of the newest members of the group, Karen, had been found dead on a Welsh mountain trail.
In a bid to identify the culprit, a determined Janie roped John into joining the group, hoping to get his insight.
However, the show's viewers were left distracted after realising that Gavin and Stacey star Melanie Walters was playing Yvonne. Melanie is best known for her role as Gwen West in the hit BBC sitcom.
Melanie wasn't the only Gavin and Stacey star to appear in the latest episode of Death Valley, with Dave Coaches actor Steffan Rhodri playing Janie's boss DCI Barry Clarke.
At the end of episode, several viewers took to X (formerly Twitter) to share their excitement after spotting the Gavin and Stacey reunion.
"Dave coaches and Gwen?! When is Nessa going to make an appearance?!" one person wrote, with another adding: "OMG Gwen and Dave Coaches!"
A third said: "Not sure I can take #DeathValley seriously what with Dave coaches as a copper & now Gwen... All we need next is Ness appearing."
Meanwhile, other viewers praised the episode, with one person sharing: "How have I never seen #DeathValley before?! It's genius!" and another writing: "Loving #DeathValley. Ludicrous, witty and quirky."
Death Valley is available to stream on BBC iPlayer
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