[Your Name, & Address here]
[Recipient Name & address here]
We invite you to a surprise party in honor of [Person’s name]. We wish to celebrate [person’s name]’s [occasion here].
It will be really a great enjoyment, but only if no one tells the [person’s name] about it.
We have chosen [place name] as the venue for the bash on [date and time]. Food and drinks will be served.
RSVP required on or before [party date]. Please call us on [phone no.].
Look forward to meet you there.