Question: “I wonder how old she is?” Answer: “She’s at an age when her back goes out more often than she does.” It’s the sort of joke that plays very well with audiences at the the Watermill’s annual dose of Seasonal Sauce.

Devised, compiled, and directed by Miss Helen Watson (all artistes are prefixed appropriately in the programme, in the old-fashioned style), Seasonal Sauce is a music hall bill of musical numbers and comedy routines. Audience participation in sing-songs is strenuously encouraged — several cast members have recently completed panto runs, so their cries of “I can’t hear you! Is there anybody out there?” are well rehearsed.

Personally I found the constant invitations to exercise our larynxes a bit repetitive, but there was no sign of this sentiment being shared by the lusty singers all around me. As in panto, it’s not a good idea to sit in the front row if you want to avoid being singled out for attention, although in panto you don’t usually get the instruction: “Stand up and show the girls your lovely moustache”.

Miss Watson (pictured) describes herself as “mistress of the single entendre”. I don’t know how many entendres you would give to: “I asked the gentleman gardener to show me his marrow. I’ve never seen one as big as that before”, but entendres don’t come much older and hoarier than that. Other comedy routines are led by bubble-curled Antony Howes – there’s an excellent take-off of TV’s Are You Being Served? while the neat send-up of The Sound of Music will be relished by those who saw the real thing at the New Theatre. Participatory or delivered from the stage, the songs zip along under pianist Martin Waddington. Lots of old music hall favourites are included, and are snappily delivered by the six-strong cast — newcomer Kate Brennan, in particular, is a name to watch for the future.

Seasonal Sauce continues until Saturday. Tickets: www.watermill.org,uk or 01635 46044.