A 30-minute bonus edition due to air next month will see Weatherfield's Sean Tully (Antony Cotton) head to the capital to be reunited with his son Dylan at the Easter holidays.
During his time away from home, Sean is both surprised and thrilled to bump into his ex-boyfriend Marcus Dent, played by Charlie Condou.
Fans will also have the chance to catch up with old Weatherfield residents as Dylan's mum Violet (Jenny Platt) and her boyfriend Jamie (Rupert Hill) both appear in the episode.
Additionally, the special sees Bruno Langley reprise his role as Todd Grimshaw as he returns to Weatherfield to introduce mum Eileen to his new rich boyfriend.
Show bosses have promised that there will be surprises in store as Todd's journey north does not go entirely to plan, while Sean's time in the capital also sparks some unexpected events.
Speaking of the special, a Coronation Street spokesperson said: "It will be a real treat for Corrie viewers to see Sean exploring the sights of London, whilst at the same time Todd returns to Weatherfield to catch up with his mum.
"Sean is desperate to be a real dad to Dylan so when Violet says he can visit he is thrilled, but when he arrives in the capital he is in for a few surprises.
"Meanwhile, back in Weatherfield, Todd has returned home for Easter - but how does he feel about Coronation Street now he has a rich boyfriend in tow and a glamorous life in London?"
Filming on the episode - due to air on Sunday, April 24 - will begin in London later this month.