Rachel's return was kept top secret as viewers saw her arrive as an unexpected witness to give evidence at Charity Macey's court trial on Tuesday night's episode (20 January).
Viewers last saw Rachel in January last year, when she fled with her son Archie after Charity blackmailed her into confessing to the fire at Home Farm, (which was actually started by Charity and Declan Macey), in order to get Sam Dingle released from prison.
Straight after last night's episode, Gemma said: "Completely & utterly overwhelmed. I can breathe again. Yep #Rachel is back... I am BACK @emmerdale and you're all amazing. Thank you x."
Fans and co-stars of Gemma took to Twitter to share their excitement, saying they were glad to see the actress return.
Having kept it a secret for just over four months, Rachel tweeted: "Sorry to all I lied to and ta to aces whom kept it quiet. That were an 'alf hard."
In her time away from the soap, 30-year-old Gemma has been campaigning for her mum and dad's eating disorder charity Seed, while also presenting a show on Capital FM in Leeds.
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