More than 20 events will take place from May 14 to 21 to showcase the wealth of talent in the town.
Many of the groups that meet on a regular basis will be relocating to the church, as will children from local schools.
Starting things off this Saturday morning will be the Young Stagers, who will have their rehearsal in the church from 10.15am to 10.45am.
In the evening, Octangle Male Voice Singers will be in concert with a blend of old and new songs to suit all tastes.
The free admission also includes sherry and shortcake.
The week will round of with a family fun day on Saturday, May 21, from 10am, with a full programme of musical acts, ending at 4pm, with Choral Evensong.
Why not also help create the largest ever street map of Horncastle during the Art and Music Festival.
Pop into the church, between 10am and 4pm, any day during the festival and put your house or business on the map.
Pens, paper and materials will be waiting.
There will also be a display of around 600 pieces of artwork to view by students from the town’s schools and the chance to enter the photographic competition to see how well you know your town.
Saturday, May 14: 10.15am - 10.45am Young Stagers rehearsal - a chance to see behind the scenes preparations for their forthcoming play; 7pm Octangle Male Voice Singers.
Sunday, May 15: 6pm Rejoice Service - refreshing service of music, sketches and fellowship.
Monday, May 16: 10.15am - 11am Blow your own trumpet - sit in on the Primary School children’s music lesson, with teacher David Chambers; 1.15pm - 1.45pm Creative Writing with QEGS students; 2pm - 2.30pm super sing-a-long with primary pupils.
Thursday, May 17: 10am Craft, colour and chat - colouring for grown ups, with tea and cake; 1pm - 2pm concert by QEGS students; 6.30pm take along your own instrument and join in with Horncastle Junior Brass Band.
Wednesday, May 18: 1pm - 2pm concert by Banovallum students; 2.30pm - 3.15pm Have-a-go on St Mary’s grand piano, with teacher Fenella Paris; Gospel Choir rehearsal, 6pm, listen and take part, before the choir’s premier at Saturday’s musical extravaganza..
Thursday, May 19: 1pm - 1.45pm concert with Lindsey Quartet & Susan Troman, followed by drum workshop, 1.45pm - 3pm.
Friday, May 20: 10am water colour painting, watch artist Ash Buckingham at work; 1pm a collection of harps - have a go.
Saturday, May 21: 10am - 4pm Family Day, with live music, workshops, competition; 4pm Choral Evensong.